• Korean Chemical Engineering Research
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• v.60 no.1
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• pp.80-85
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• 2022

In wastewater treatment processes huge quantities of sludge are produced continuously each year. This work investigated the reuse of two types of sludge as biosorbents of a toxic dye. The potential of granular and filamentous fungus dried sludge for the elimination of eosin from aqueous solution was studied in batch system. The effect of initial concentration and temperature was examined. Maximum uptake was observed at 100 mg l^-1 and 30 ℃. The maximum removal rate was 92% for the granular sludge and 90% for the filamentous one. Equilibrium was attained after 30 min for the studied dye concentrations. The equilibrium uptake increased with the initial eosin concentration. The Freundlich and Langmuir adsorption models were also investigated. The reuse of disposed sludge as adsorbent could be a solution for the valorization of such dangerous waste to resolve two environmental problems at the same time.

• Korean Journal of Soil Science and Fertilizer
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• v.13 no.4
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• pp.115-118
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• 1981

Effect of water potential of culture solution on photosynthesis, transpiration and water uptake was investigated using polyethylene glycol 6000. 1. Even at -0.5 bar of culture solution phothosynthesis was decreased by 20% within 1 hour. Plant in control showed 3.26% loss of initial water for 13 hours suggesting very sensitive in water uptake. 2. Relation between water potential of culture solution (${\psi}$) and water uptake amount (W) 2-year root was ${\psi}=-2.890/e^{2.796W}$ indicating that permanent wilting point will be greater than -2.89 bar. 3. Transpiration considerably decreased with the decrease of water potential and thus by 23.9% at -0.5 bar after 4 hours. 4. From the above results ginseng plant appears to have high root water potential at permanent wilting point and thus very week to water stress due to drought or high salt content in soils.

• Journal of Bio-Environment Control
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• v.7 no.1
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• pp.63-70
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• 1998

This study was carried out to investigate the interaction of selenate and sulfate ion in nutrient solution supplyed with selenate ion. At early growth stage, the growth of Mongolian wormwood was best at 3mM sulfate ion and 2mg/$\ell$Na$_2$SeO$_4$ treatment. As they were grown and matured, at the later growth stage, the effect of antagonism between selenate and sulfate ion on the growth of each plant decreased. At supplying with selenate ion in nutrient solution, the uptake of selenate by plant had negative correlation with sulfate ion concentration in nutrient solution. The higher sulfate ion concentration, the less selenium uptake. However, the effect of antagonistic interaction of selenate and sulfate ion on the selenium uptake increased with plant age. Whereas, the uptake of sulfate ion had positive correlation with sulfate ion concentration in nutrient solution at supplying with selenate ion in nutrient solution. The uptake of sulfate ion increased with increase of sulfate ion concentration in nutrient solution. The effect of this interaction with selenate and sulfate ion increased with growth and maturity of plant. However, at 3mM sulfate ion concentration in nutrient solution, sulfate ion concentration in plant tissue decreased markedly.

• Journal of Environmental Science International
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• v.8 no.3
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• pp.387-391
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• 1999

$Pb^{2+}$ and $Cr^{3+}$ uptake capacity by Sargassum horneri was 185.5 mg $Pb^{2+}$/g biomass and 102.6 mg $Cr^{3+}$/g biomass, respectively. An adsorption equilibria were reached within about 0.5 hr for $Pb^{2+}$ and 1 hr for $Cr^{3+}$. The adsorption parameters for $Pb^{2+}$ and $Cr^{3+}$ were determined according to Langmuir and Freundlich model. With an increase in pH values of 2 to 5, $Pb^{2+}$ uptake was increased, however $Cr^{3+}$ uptake jwas constant. The selectivity of mixture solution showed the uptake order of $Pb^{2+}$>$Cu^{2+}$>$Cr^{3+}$>$Cd^{2+}$. $Pb^{2+}$ and $Cr^{3+}$ adsorbed by S. horneri could be recovered from 0.1M HCl, 0.1M ${HNO}_3$ and 0.1M EDTA by desorption process, and the efficiency of $Pb^{2+}$ desorption was above 98%, whereas the efficiency of $Cr^{3+}$ desorption was below 34%.

• Environmental Engineering Research
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• v.21 no.2
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• pp.203-210
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• 2016

Hybrid materials were obtained modifying the bentonite (BC) and local clay (LC) using hexadecyltrimethylammonium bromide (HDTMA) or the clay were pillared with aluminum followed by modification with HDTMA. The materials were characterized by the SEM, FT-IR and XRD analytical tools. The batch reactor data implied that the uptake of $17{\beta}$-estradiol (E2) by the hybrid materials showed very high uptake at the neutral pH region. However, at higher and lower pH conditions, slightly less uptake of E2 was occurred. The uptake of E2 was insignificantly affected changing the sorptive concentration from 1.0 to 10.0 mg/L and the background electrolyte (NaCl) concentrations from 0.0001 to 0.1 mol/L. Moreover, the sorption of E2 by these hybrid materials was fairly efficient since within 30 mins of contact time, an apparent equilibrium between solid and solution was achieved, and the data was best fitted to the PSO (pseudo-second order) and FL-PSO (Fractal-like-pseudo second order) kinetic models compared to the PFO (pseudo-first order) model. The fixed-bed column results showed that relatively high breakthrough volume was obtained for the attenuation of E2 using these hybrid materials, and the loading capacity of E2 was estimated to be 75.984, 63.757, 58.965 and 49.746 mg/g for the solids BCH, BCAH, LCH and LCAH, respectively.

• Journal of Ecology and Environment
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• v.34 no.4
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• pp.393-400
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• 2011

The effects of the ectomycorrhizal fungus Pisolithus tinctorius and cadmium (Cd) on physiological properties and Cd uptake by Populus alba ${\times}$ glandulosa was investigated under greenhouse conditions. Cd treatment decreased the photosynthetic rate ($P_N$) of both non-mycorrhizal (NM) plants (16.3%) and ectomycorrhizal (ECM) plants (11.5%). In addition, the reduction in total dry weight by Cd treatment was greater in ECM plants (24.3%) than that in NM plants (17.6%). Mycorrhizal infection increased the $P_N$ and transpiration rate in both control and Cd-treated plants. Cd treatment increased superoxide dismutase (SOD) activity and decreased glutathione reductase activity, and the increase of SOD activity by Cd treatment was greater in NM plants (40.3%) than that in ECM plants (3.7%). Thiol content increased in both NM and ECM plants treated with Cd solution, and the increase in thiol content in NM plants (43.9%) was greater than that of ECM plants (15.6%). Cd uptake in the leaves, stems, and roots of ECM plants was 69.9%, 167.2% and 72.8%, respectively, higher than in the NM plants. However, the increase in Cd uptake ability of ECM plants resulted in a reduction in dry weight.

• Biotechnology and Bioprocess Engineering:BBE
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• v.2 no.2
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• pp.132-135
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• 1997

We prepared capsules containing Saccharomyces cerevisiae and Zoogloea ramigera cells for the removal of lead(II) and cadmium ions. Microbial cells were encapsulated and cultured in the growth medium. The S.cerevisiae cells grown in the capule did not leak through the capsule membrane. The dried cell density reached to 250 g/l on the basis of the inner volume of the 2.0 mm diameter capsule after 36 hour cultivation. The dry whole cell expolymer density of encapsulated Z.ramigera reached to 200 g/L. The capsule was crosslinked with triethylene tetramine and glutaric dialdehyde solutions. The cadmium uptake of encapsulated whole cell expolymer of Z.ramigera was 55mg Cd/g biosorbent. The adsorption line followed well Langmuir isotherm. The lead uptake of the encapsulated S. cerevisiae was about 30 mg Pb/g biomass. The optimum pH of the lead uptake using encapsulated S. cerevisiae was found to be 6. Freundlich model showed a little better fit to the adsorption data than Langmuir model 95 percent of the lead adsorbed on the encapsulated biosorbents was desorbed by the 1 M HCl solution. The capsule was reused 50 batches without loosing the metal uptake capacity. And the mechanical strength of the crosslinked capsule was retained after 50 trials.

• Journal of Bio-Environment Control
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• v.7 no.3
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• pp.206-213
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• 1998

This experiment was conducted to investigate the effects of concentration of NO$_{3}$$^{[-10]}$ , $K^{＋}$ and $Ca^{＋＋}$ in nutrient solution on the seedlings growth of ‘Mudeungsan’watermelon. Seeds were sown on March 16, 1997. NO$_{3}$$^{[-10]}$ , $K^{＋}$ and $Ca^{＋＋}$ was treated with three different levels, respectively, NO$_{3}$$^{[-10]}$ = 106, 206, 406ppm; $K^{＋}$ = 150, 200, 400 ppm; $Ca^{＋＋}$ = 150, 200, 400 ppm. Plant growth was investigated at four-days interval in 10 days after treatment. Increasing N concentration in the nutrient solution increased the plant height, leaf area, number of leaves, fresh and dry weight of shoot while high concentration of K and Ca in the nutrient solution decreased the seedling growth in terms of leaf area, leaf dry weight. The uptake of N, K and Mg in petiole sap was positively affected by the adding of 206 ppm of nitrate, 150 ppm of potassium and 200 ppm of calcium levels, respectively. The P and Ca uptake in petiole sap was not affected by the N and K concentrations in the nutrient solution while K concentration above 200 ppm decreased the N and Mg content in petiole sap. High concentration of Ca in the nutrient solution increased the Ca content in petiole sap while Ca concentration above 200 ppm decreased the N content.

• Journal of Bio-Environment Control
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• v.10 no.3
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• pp.133-140
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• 2001

This study was conducted to develop a nutrient uptake model in cucumnber (Cucumis sativus L. cv. Eunsung Backdadagi) plants for prediction of the amount of nutrients in drainage solution in a closed perlite culture system. Electrical conductivity (EC) of the nutrient solution was adjusted to 1.5, 1.8, 2.1, 2.4, and 2.7 dS. $m^{-1}$ . The amount of nutrient solution absorbed in different EC treatments was not different until the mid stage of growth. However, after the mid growth stage, a high EC treatment resulted in less solution absorption. The absorption rates of K, N $O_3$$^{[-10]}$ -N, Mg, and P increased continuously for a whole growing period in all treatments, while those of Ca decreased slightly. For S, the decrease was significant after th mid stage of growth. although the amounts of absorbed inorganic ions in different EC treatments were not significantly different at the first stage of growth, they were significantly different after the mid stage of growth and decreased slightly at the end of growth stage. Models for predicting the amounts of each inorganic ion absorbed were developed by using EC and the amount of nutrient solution absorbed per unit radiation(mg.M $J^{-1}$), which proved to be practical with a positive correlation at 1 percent probability between the developed model and practical values..

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.1
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• pp.22-29
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• 2015

The objectives of this study were to monitor the changes in soil solution nutrients and to evaluate their effect on rice uptake and yield. The changes of chemical characteristics of paddy soil solution were examined from the 58th fertilization experiment in which the continuous rice cropping experiment started in 1954 at the National Academy of Agricultural Science. The treatments were no fertilization (No fert.), inorganic fertilization (NPK), inorganic fertilizer plus rice straw compost (NPKC) and inorganic fertilizer plus silicate and lime fertilizer as a soil amendment (NPKCLS). The fertilizers were added at rates of standard fertilizer application rate in which nitrogen (N), phosphate ($P_2O_5$), potassium ($K_2O$), and sililcate ($SiO_2$) were applied at rates of $75{\sim}150kg\;ha^{-1}$, $70{\sim}86kg\;ha^{-1}$, $75{\sim}86kg\;ha^{-1}$, and $7.5Mg\;ha^{-1}$ respectively and lime was applied to neutralize soil acidity until 6.5. Average Electrical Conductivity (EC) of soil solution in NPKCLS and NPKC ranged from 1.16 to $2.00dS\;m^{-1}$. The $NH{_4}^+$ and $K^+$ levels in NPKCLS and NPKC were higher than that of the other treatments, due to high supply power of rice straw compost. The content of $H_3SiO{_4}^-$ was higher in NPKCLS because of silicate application. The dominant ions in soil solution were $Ca^{2+}$, $Mg^{2+}$ and $Na^+$ among cations and $HCO{_3}^-$, $SO{_4}^{2-}$, and $Cl^-$ among anions in all treatments. The continuous application of inorganic fertilizers plus rice straw compost (NPKC) and silicate fertilizer (NPKCLS) led to the changes of various chemical composition in soil solutions. Also, they had a significant impact on the improvement of rice inorganic uptake and grain yield. Especially, inorganic uptake by rice in NPKC and NPKCLS significantly increased than those in NPK plot; 14~46% for T-N, 32~36% for P, 43~57% for K, and 45~77% for Si. Therefore, the combined application of inorganic fertilizers with organic compost as a soil amendment is considered as the best fertilization practice in the continuous rice cropping for the improvement of crop productivity and soil fertility.