• Journal of the Korean institute of surface engineering
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• v.33 no.2
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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.

• Journal of Environmental Science International
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• v.28 no.8
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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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• v.10 no.1
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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.

• Journal of Soil and Groundwater Environment
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• v.26 no.6
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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.

• Electrical & Electronic Materials
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• v.1 no.1
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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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• v.20 no.4
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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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• v.11 no.2
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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.

• Journal of the Korean Electrochemical Society
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• v.26 no.3
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• pp.35-41
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• 2023

The carbon-coated silicon monoxide (c-SiO_x), which is a negative electrode active material for lithium-ion batteries (LIBs), has a limited cycle performance due to severe volume changes during cycles, despite its high specific capacity. In particular, the significant volume change of the active material can deform the electrode structure and easily damage the electron transfer pathway. To improve performance and mitigate electrode damage caused by volume changes, we replaced parts of the carbon black conducting agent with carbon nanotubes (CNTs) having a linear shape. The content of the entire conductive material in the electrode was fixed at 10% by mass, and the relative content of CNTs ranged from 0% to 25% by mass to prepare electrodes and evaluate electrochemical performance. As the CNT content in the electrode increased, both cycle life and rate capability improved. Even a small amount of CNT can significantly improve the electrochemical performance of a c-SiO_x negative electrode with large volume changes. Furthermore, dispersing CNTs effectively can lead to achieving the equivalent performance with a reduced quantity of CNTs.

• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.300-306
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• 1989

Physico-chemical changes caused by salting Korean radish cubes (for Kakdugi) with sodium chloride solution were investigated. Two-centimter cubes of Korean radish were soaked in saline solution of 5, 10, 15, 20 and 25 percent concentration. Optimum salinity, 3% as determined by taste, was reached in six hours at 5% strength, two hours in 10%, one hour at 15% and within one hour at concentration of 15% plus. Radish cubes salted in 5, 10. 15, 20 and 25% sodium chloride solution in a cube/solution weight ratio of 1:1 decreased in volume from 7.6 to 11.2% after one hour, and from 11.2 to 17.9% after six hours. Decrease in moisture content was from 83.0 to 75.9% in one hour and from 74.5 to 68.5% after six hours. $Potassium\;ion(K^+)$, $calcium\;ion(Ca^{2+})$ and $magnesium\;ion(Mg^{2+})$ content was significantly decreased by salting, but $sodium\;ion(Na^+)$ content greatly increased. In addition, salting caused firmness of the cubes to decrease, and cell shapes to shrink by plasmolysis.

• Journal of Ecology and Environment
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• v.35 no.4
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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.