• The Korean Journal of Ecology
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• 제16권2호
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• pp.169-180
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• 1993

Soils of four combinations, sand with high content of organic matter(SL), sand with low content of OM(SS), siltyl loam with high content of OM(LL) and silty loam with low content OM (LS), were filled on column and then percolated with simulated sulfuric acid rain with pH 5.6, 4.0, 3.5, 3.0 and 2.5. From soil leachates, pH and concentrations of basic cations and Al were determined. Cation concentrations in the leachates increased as pH of the rain decreased. The orders of buffering capacity of soil, leachability of cation from soil, leaching sensitivity of ion andbase saturation sensitivity of soil to acidity of the rain water were SS$\leq$K <$\leq$LL

• 한국산림과학회지
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• 제96권1호
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• pp.14-20
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• 2007

구상나무의 스트레스 적응능력을 보여주는 항산화효소활성, 건전개체와 쇠약한 개체의 토양의 물리화학적 특성을 알아보기 위하여 윗세오름, 영실 그리고 성판악(진달래밭)지역의 건전개체와 쇠퇴개체를 조사 분석하였다. 항산화효소활성으로는 Ascorbate peroxidase(APX)와 Glutathione Reductase(GR)를, 토양특성으로는 토성, pH, 유기물함량, 전 질소함량, 유효인산, 양이온치환용량, 양이온의 함량을 분석하였고, 구상나무 잎을 채취하여 식물체의 양분함량을 분석하였다. APX, GR 효소 활성에 있어서 건전개체와 쇠약한 개체 사이에는 큰 차이가 없었으나, 계절적으로 6월과 8월에 비해 9월의 항산화효소 활성도가 낮게 나타났다. 토양분석 결과 유기물함량, 전질소, 유효인산, 양이온치환용량, 양이온 함량이 건전개체가 있는 곳에 비해 쇠약한 개체가 있는 곳의 토양이 낮게 나타났다.

• Korean Chemical Engineering Research
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• 제56권3호
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• pp.361-369
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• 2018

A manufacturing method has been devised to prepare novel heterogeneous cation exchange membranes by mixing ethylene vinyl acetate (EVA) copolymers with a commercial cation exchange resin. Optimum material characteristics, mixture ratios and manufacturing conditions have been worked out for achieving favorable membrane performance. Ion exchange capacity, electrical resistance, water uptake, swelling ratio and tensile strength properties were measured. SEM analysis was used to monitor morphology. Effects of vinyl acetate (VA) content, melt index (MI) and ion exchange resin content on properties of heterogeneous cation exchange membranes have been discussed. An application test was carried out by mounting a selected membrane in a membrane capacitive deionization (MCDI) system to investigate its desalination capability. 0.92 meq/g of ion exchange capacity, $8.7{\Omega}.cm^2$ of electrical resistance, $40kgf/cm^2$ of tensile strength, 19% of swelling ratio, 42% of water uptake, and 56.4% salt removal rate were achieved at best. VA content plays a leading role on the extent of physical properties and performance; however, MI is important for having uniform distribution of resin grains and achieving better ionic conductivity. Overall, manufacturing cost has been suppressed to 5-10% of that of homogeneous ion exchange membranes.

• 한국토양비료학회지
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• 제42권3호
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• pp.187-191
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• 2009

'Campbell Early', a major grape cultivar, occupies more than 70% of cultivated vineyard areas, however, recommendable standard management system of soil environmental conditions has not been developed yet in Korea. The consideration for the correlation between fruit quality and soil condition in the vineyard is required in the efficient management system of soil. This study was carried out to investigate the optimum soil environmental conditions for 'Campbell Early' grape production with high quality. The results from analyses of correlation between them were used to develop soil management guideline for promoting efficiency in grape production. Soil properties were analyzed from 120 vineyards in Hawsung, Sangju, Yeongdong, Gimcheon, Yeongju, and Yeongwol, major grape production regions. Because there is neither coloring disorder nor delayed coloration in grape production of 'Campbell Early', relative contribution of soil hardness and solid phase to fruit quality and fruit weight was analyzed. Among the soil properties, while cation and soil hardness affected sugar content at the level of 39.3% and 36.8%, respectively, saturated hydraulic conductivity, solid phase, and cation exchange capacity (CEC) showed relatively low contribution to sugar content in the vineyard. The sugar content in grapes was influenced more critically by the chemical properties than the physical ones in the soil of vineyards. While soil hardness and solid phase affected grape weight at the level of 27.8% and 26.0%, respectively, phosphate content, organic matter content, and cation showed low contribution to grape weight. Grape guality such as sugar content and grape weight was affected highly by cation and organic matters. Therefore, cation and organic matter content of soil contributed to fruit quality at the level of 33.8% and 15.5%, respectively, in the vineyard.

• 한국자원식물학회지
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• 제34권6호
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• pp.566-574
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• 2021

This research was carried out to investigate the correlation between soil chemical properties and bioactive compounds of Acer tegmentosum Maxim. The methods of determining bioactive compounds were determined by high performance liquid chromatography, that contained (-)-gallocatechin (0.04±0.01 ~ 0.43±0.28%), salidroside (0.90±0.06 ~ 3.86±0.59%), tyrosol (0.03±0.00 ~ 0.43±0.00%), (-)-catechin (0.05±0.01 ~ 0.37±0.14%), 6'-O-galloylsalidroside (0.02± 0.01 ~ 0.31±0.06%), (-)-epicatechin-gallate (0.01±0.00 ~ 0.04±0.01%). The soil chemical properties analysis such as soil pH, electric conductivity (EC), organic matter (OM), total nitrogen (TN), available phosphate (Avail. P₂O₅), exchangeable cation and cation exchange capacity (CEC) were performed following the standard manual. The correlation analysis between soil chemical properties and bioactive compounds of A. tegmentosum, soil pH, available phosphate and exchangeable cation (Ca²⁺ and Mg²⁺) were negatively correlated with content of salidroside. On the other hand, soil exchangeable cation (Na⁺) showed positive correlation with content of salidroside. The results of this study was able to investigate the correlation between soil chemical properties and bioactive compounds of A. tegmentosum.

• 한국토양비료학회지
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• 제43권6호
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• pp.782-788
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• 2010

Detail management standard on soil conditions in 'Kyoho' grapes were not yet made. Therefore, this study was carried out to investigate the optimum soil environmental conditions on production of high fruit quality in 'Kyoho' grapes. We established using correlation between fruit quality and soil condition. These results were used to develop soil management guideline with promoting efficiency and minuteness in grape vineyard. Soil conditions were analyzed at total 80 vineyards in major grape producing areas such as Ansung, and Cheonan (40 orchards an area). The soil environmental factors affected fruit weight were soil pH of 36.6%, cultivation layer depth of 23.3%, and cation of 17.8%. The soil condition factors affected sugar content were soil hardness of 24.4%, cation of 24.1% and organic matter content of 22.1%. Cultivation layer depth, soil texture, and phosphate content were low as relative contribution. Coloring was involved with organic matter content, CEC (cation exchange capacity), and saturated hydraulic conductivity. while soil pH, cultivation layer depth, and phosphate content showed low contribution. Finally, relative contribution on fruit quality related with sugar content, fruit weight, and coloring were soil hardness of 28.0%, organic matter content of 25.0%, soil pH of 12.9%.

• 상하수도학회지
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• 제22권5호
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• pp.561-569
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• 2008

We analyzed contents of cations and anions for the domestic bottled drinking water. Results showed that total cation content was 45.81 mg/L and contained 40% of Ca. The content of cations were decreased in the order of Ca>Si>Na>Mg>K. Total anion content was 12.20 mg/L and contained 90% of ${SO_4}^{2-}$ and $Cl^-$. $F^-$ and $NO_{3-}N$ were a little contained. While Si content was reduced 2.3~75.7%(mean value:38.5%) after freezing, Ca content was reduced 45.2% after boiling. It showed that water containing higher Ca content was significantly decreased after boiling. Precipitates formed by freezing and boiling is composed of minerals such as Si and Ca. Compared to minerals from food intake, concentrations of minerals from water intake are expected to be less influenced. It is recommended Bottled Water that contains more than 20 mg/L of Ca(exceeding water-quality standard for turbidity) is safe to drink without thawing and boiling.

• 한국응용과학기술학회지
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• 제23권1호
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• pp.45-53
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• 2006

In this study, we prepared porous cation exchange membrane using polystyrene such as, EPS (expanded polystyrene), SAN (styrene acrylonitrile copolymer) and HIPS (high impactive polystyrene). These polystyrenes were sulfonated by acetyl sulfate to make porous cation exchange membrane such as, SEPS, SSAN, SHIPS. SEM was employed to confirm porous structure of membrane, and IR spectroscopy was used to confirm sulfonation rate of ion exchange membrane. Water and methanol content were also increased with amount of sulfuric acid in reactants. SSAN-20 showed the highest value in water and methanol content. Fixed ion concentration and conductivity was also increased with an amount of sulfuric acid in reactants. Methanol permeability for SEPS-20, SSAN-20, SHIPS-20 was found to be $1.326\;{\times}\;10^{-5}\;cm^2/s$, $1.527\;{\times}\;10^{-5}\;cm^2/s$ and $1.096\;{\times}\;10^{-5}\;cm^2/s$ respectively. From the result of electrodialysis experiment in 0.03 M $Pb(NO_3)_2$ aqueous solution, anion exclusion and cation selection effects were confirmed.

• 패션비즈니스
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• 제5권2호
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• pp.67-72
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• 2001

Tencel fabric was treated with cellulase and softener. And then Mechanical properties were investigated. Basic characteristic values of clothing wearing were calculated. With the treatment of cellulase and softener treatment, WT, RT, LC, WC, RC of mechanical characteristics were increased, and G, 2HG, 2HG5, B, 2HB were decreased. B/W, $\sqrt[3]{B/W}$, $\sqrt{2HB/W}$, 2HB/B, W/T of Basic characteristic values of clothing wearing were decreased. WC/W, WC/T were increased, Therefore, drapability, crease resistance, pressing softness, air content were improved. In consideration of mechanical characteristics and basic characteristic values of clothing wearing depending on the softener, values of WT, WC/W, WC/T were bigger with the treatment of epoxy and snow softener than with the treatment of cation and blend softener. LC, WC, RC, B/W, $\sqrt[3]{B/W}$, $\sqrt{2HB/W}$, 2HB/B, W/T were bigger with the treatment of cation and blend softener than with the treatment of epoxy and snow softener. Thereofre, with the treatment of epoxy and snow softener, drapability, crease resistance, air content were improved. With the treatment of cation and blend softener, pressing softness were improved.

• Bulletin of the Korean Chemical Society
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• 제11권4호
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• pp.276-281
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• 1990

The equivalent conductance of univalent cation (potassium, silver, thallium and ammonium) perchlorates in methanol containing 18-membered crown ethers, 18-crown-6 (18C6) and 1,10-dithia-18-crown-6 (DT18C6) were measured at different temperatures. The equivalent conductances of ammonium perchlorate were increased by increasing content of DT18C6 exceptionally, due to more favorable solvations than complexations. From the equivalent conductance changes, the formation constants for 1:1 compmlexes have been determined, and the values of enthalpy and entropy changes have been calculated. The complexations of 18C6 and DT18C6 with the univalent cations under investigation are all exothermic and the ${\Delta}$S values are all negative and no considerable differences around 50 J/ (k mol). The selectivity order of 18C6 is $K^+ > Tl^+ > Ag^+ > NH_4^+$, while that of DT18C6 is $Ag^+ > Tl^+ > NH_4^+ > K^+$. By sulfur substitutions in 18C6 result in significant decrease in stability, but the stability of $Ag^+$-DT18C6 complex are $10^4$ times larger than those of $K^+$. This increase of stabilities for $Ag^+$-DT18C6 complex are primary due to the result of favorable exothermic heat of reaction between the polarizable soft cation and soft sulfur centers. In NMR experiment, the stepwise additions of cation perchlorates into crown ether solutions induced two major spectral changes. First, the resonance all shift down field and the cation induced shifts were linear up to 1:1 cation/crown ratio, above which no further changes were observed. On the basis of these results, it could be concluded that 1:1 complex is formed. Second, the magnitudes of cation induced shifts were different each other in same ligand. By addition of silver ion to the solution of DT18C6, the largest shift of proton peak near the sulfur atom was observed. These effects are also arisen from the results of covalent bonding between "soft-soft" interactions.