• 한국표면공학회지
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• 제33권2호
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• pp.115-125
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• 2000

TiN films were deposited onto Stellite 6B alloy (Co base) by the reactive magnetron sputter ion plating. As the bias increases, TiN film changes from columnar structure to dense structure with great hardness and smooth surface due to densification and resputtering by ion bombardment. The content of oxygen and carbon impurities in the TiN film decreases greatly when the substrate bias is applied. The preferred orientation of the TiN films changes from (200) to (111) with decreasing $N_2$/Ar ratio, and from (200) to (111) and then (220) with increasing the substrate bias. The change of the preferred orientation is discussed in terms of surface energy and strain energy which are related to the impurity contents and the ion bombardment damage. The hardness of the TiN film increases with increasing compressive stress generated in the film by virtue of ion bombardment. It becomes as high as up to 3500kgf/mm$^2$ when an appropriate substrate bias is applied.

• 한국환경과학회지
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• 제28권8호
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• pp.677-687
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• 2019

This study evaluated the biosorption properties of calcium ion using Aerobic Granular Sludge (AGS). A sequencing batch reactor was used to induce the production of Extracellular Polymeric Substances (EPS) through salinity injection, and the calcium ion adsorption efficiency was analyzed by a batch test. The EPS contents showed significant changes (104-136 mg/g MLVSS) at different salinity concentrations. The calcium ion adsorption efficiency was highest for AGS collected at 5.0% salinity, and it was confirmed that the biosorption efficiency of AGS was increased owing to the increase in EPS content. The results of the Freundlich isotherms showed that the ion binding strength (1/n) was 0.3941-0.7242 and the adsorption capacity ($K_f$) was 2.4082-3.3312. The specific surface area and the pore size of the AGS were $586.1m^2/g$ and 0.7547 nm, respectively, which were not significantly different from each other. It was confirmed that the influence of biological properties, such as EPS content, was relatively large among the factors affecting calcium ion adsorption.

• Journal of Crop Science and Biotechnology
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• 제10권1호
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• pp.39-44
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• 2007

The effect of inabenfide was investigated in rice seedlings subjected to salt stress in relation to changes in chlorophyll fluorescence(${\Delta}F/Fm'$), lipid peroxidation, salicylic acid(SA) content, and catalase(CAT) activity. A reduction in shoot growth of rice seedlings by 120 mM NaCl treatment was significantly alleviated by pretreatment with 30 ${\mu}M$ inabenfide. Sodium ion content was not affected by pretreatment with inabenfide, suggesting that alleviation was not due to a reduction in sodium ion uptake by the rice seedlings. At three days after NaCl treatment, the rice seedlings pretreated with inabenfide showed a higher ${\Delta}F/Fm'$(30%) and lower lipid peroxidation(28%) compared with the rice seedlings treated with NaCl alone. After NaCl treatment, CAT activity in the third leaf of rice seedlings decreased significantly but alleviated by pretreatment with inabenfide. Furthermore, pretreatment with inabenfide also reduced the level of SA which accumulated drastically in the third leaf of rice seedlings within a day after exposure to salt stress. These results suggest that inabenfide prevents SA accumulation in rice seedlings under salt stress which eventually induces the alleviation of salt stress damage.

• 한국지하수토양환경학회지:지하수토양환경
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• 제26권6호
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• pp.157-164
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• 2021

Smart agriculture requires sensing systems which are fundamental for precision agriculture. Adequate and appropriate water and nutrient supply not only improves crop productivity but also benefit to environment. However, there is no available soil sensor to continuously monitor nutrient status in soil. Electrical conductivity (EC) of soil is affected by ion contents in soil and can be used to evaluate nutrient contents in soil. Comparison of various commercial EC sensors showed similar water content and EC values at water content less than 20%. Soil EC values measured by sensors decreased with decreasing soil water content and linearly correlated with soil water content. EC values measured by soil sensor were highly correlated with water soluble nutrient contents such as Ca, K, Mg and N in soil indicating that the soil EC sensor can be used for monitoring changes in plant available nutrients in soil.

• E2M - 전기 전자와 첨단 소재
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• 제1권1호
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• pp.70-77
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• 1988

This paper describes the influence of the electrode materials, moisture content, electrolyte density, temperature, surface state, ion absorbent on the C.T.I of phenolic resin by the I.E,C, 112 method. C.T.I are increased for electrode materials with low hydrogen overvoltage and high soluble point. Increusing moisture content of samples increased by logarithmical on the droplet number to tracking breakdown. Increasing electrolyte temperature region above 70-80(.deg.C) decreased hydrogen over-voltage, following the density changes are decreased by C.T.I=1/aD$^{2}$-bD+C.

• The Korean Journal of Ecology
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• 제20권4호
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• pp.275-283
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• 1997

Vertical and temporal characteristics of desalinized reclaimed soil were analyzed from reclaimed coastal land on the western coast of Korea. Of the vertical changes during desalting, pH valuse were the lowest at the topsoil without regard to reclaimation time. The content of C1 were designated as the early period (the first 2-4 years) which decreased exponentially and the later period(the last 5-7 years) which was almost constant, from top to down. In temporal changes of the soil attributes, pH values increased for 5 years and decreased at 6 year after reclamation. Chlorine leaches more rapidly than Na does, K and Ca are constant but Mg increases as time elapsed after reclamation. Sometimes the content of Ca and K in the reclaimed soil are of higher concentration than that of the seawater after reclamation. During desallinization as exemplified by decreasing EC of the soil, Cl and Na are rapidly leached, but K, Ca and Mg are somewhat enhanced. The ration of Na/Cl in the soil equals 1 when the EC registers 5 mmho and then increases dramatically as the EC decreases. Rapid leaching of $Cl^{-}$ elicits an increasing pH valus. The electrostatic balance of the soil is achived by replacement of $Cl^{-}$ with $OH^{-}$ until stationary or until a decreasing pH value is reached again.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권2호
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• pp.121-126
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• 2006

Saikosaponin productivity was examined in a Bupleurum falcatum L. BFHR2 hairy root culture in response to changes in the sucrose content $(2{\sim}8%)$, nitrogen content $(0{\sim}250mM\;NH_4NO_3)$, phosphate content $(0{\sim}12mM\;NaH_2PO_4)$, and the potassium content $(0{\sim}87.2 mM\; KCl)$ of the culture media. We found that the conditions for maximal saikosaponin production differed from those for optimal root growth. Highest saikosaponin yield was achieved for 8% sucrose, 62mM $NH_4NO_3$ 1.2 mM $NaH_2PO_4$, and 0.5mM KCl.

• 전기화학회지
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• 제26권3호
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• pp.35-41
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• 2023

리튬이온 이차전지용 음극 활물질인 탄소가 코팅된 실리콘 일산화물(carbon-coated silicon monoxide, c-SiO_x)은 용량이 높지만, 충방전 중의 부피변화로 인해 사이클 수명이 제한된다. 특히, 활물질의 큰 부피 변화는 전극의 구조를 변형시켜 전자의 전달경로가 쉽게 손상될 수 있다. 전극에서 전자전달 경로를 형성하는 도전재인 카본블랙 중 일부를 선형의 형태를 지니는 탄소나노튜브(carbon nanotube, CNT)로 대체하여 활물질의 부피변화로 인한 전극의 손상을 완화하여 성능을 개선하고자 한다. 전극 내의 전체 도전재의 함량을 10 중량%로 고정하고, 탄소나노튜브의 상대적인 함량을 0, 2, 5, 10, 25 중량%로 카본블랙의 일부를 대체하여 전극을 제조하고 전기화학적 성능을 평가하였다. 전극 내의 탄소나노튜브의 함량이 증가함에 따라 사이클 수명과 속도특성이 모두 향상된다. 부피 변화가 큰 c-SiO_x 음극에 소량의 CNT를 도전재로 적용하는 것으로 전지의 전기화학적 성능을 크게 향상시킬 수 있다. 또한 CNT를 잘 분산시키게 되면 더 적은 양을 사용하면서도 동등한 성능을 구현할 수 있다.

• 한국식품과학회지
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• 제21권2호
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• pp.300-306
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• 1989

간절임 공정이 깍두기용 무우 cube의 이화학적인 성질에 미치는 영향을 조사하기 위하여 무우 $cube(2cm^3)$를 5, 10, 15, 20, 25%의 소금용액에서 간절임 (무우 cube: 소금용액=1: 1w/w) 하는 동안 일어나는 염도, 수분함량, 형태, 부피, 무기물함량,조직 및 경도변화를 조사하였다. 깍두기의 간에 맞는 최적 염도(3%)는 5%에서 6시간, 10%에서 2시간, 15%에서 1시간 그리고 15% 이상에서는 1시간 이내에 도달되었으나 표층의 염도와 내층의 염도에 차이가 있었다. $5{\sim}25%$의 소금용액에서 간절임 된 무우 cube의 부피는 간절임 1시간 동안 원래 부피의 $7.6{\sim}11.2%$가, 6시간 동안에는 $11.2{\sim}17.9%$가 줄었다. 그리고 수분함량은 간절임 1시간 동안에 $83.0{\sim}75.9%$ 수준으로, 6시간 후에는 $74.5{\sim}68.5%$ 수준으로 감소되었다. 간절임중 무우 cube의 $K^+$, $Ca^{2+}$, $Mg^{2+}$ 함량은 소금용액의 농도$(5{\sim}25%)$에 따라서 간절임 1시간 내에 각각 $87{\sim}131mg%$, $35{\sim}75mg%$, $17{\sim}32mg%$로, 6시간 내에 각각 $63{\sim}105mg%$, $20{\sim}49mg%$, $6{\sim}10mg%$ 정도로 감소한 반면 $Na^+$ 함량은 1시간 내에 $815{\sim}1207mg%$로, 6시간 이내에 $1204{\sim}1307mg%$로 증가되었다. 간절임에 의한 무우 cube의 세포는 수축되었고, 물성 (견고성을 기준)은 무우 세포로부터 탈수와 가교결합형 $Ca^{2+}$ 와 $Mg^{2+}$용출로 인하여 전체적으로 크게 감소하였다.

• Journal of Ecology and Environment
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• 제35권4호
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• pp.351-358
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• 2012

To investigate the environmental adaptation and ecophysiological characteristics of Suaeda maritima and S. asparagoides under saline conditions, plant growth and density were analyzed according to environmental changes of habitats. The total ion content of soil decreased with time, which was caused by the predominance of exchangeable $Na^+$ and $Cl^-$ in the upper layers. The population of S. maritima was more densely distributed in the region with higher ion contents of $Cl^-$, $Mg^{2+}$, $K^+$ and $Na^+$ than the population of S. asparagoides. Both species were showed a decreased population density according to increases in plant growth. Under the conditions of a salt field, S. maritima and S. asparagoides contained high inorganic ions to maintain low water potential, but low water soluble carbohydrate contents. In the case of free amino acid, S. maritima showed an especially high proline content, and contained rather large amounts of free amino acids, whereas S. asparagoides did not. Both species showed high inorganic ion contents in the leaves, which might be a mechanism of avoiding the ionic toxicity by diluting the accumulated ionic concentration with a high ratio of water content to dry weight. This result suggests that S. maritima seems to adapt to saline conditions by accumulating proline in addition to inorganic ions. S. asparagoides seems to adapt by osmoregulation processes, using inorganic ions rather than free amino acids.