• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.09a
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• pp.75-78
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• 2001

Authors evaluated the feasibility of a permeable reactive biobarrier (PRB) treated with biofilm formed by Beijerinckia indica (B.indica). This study focused on evaluating two potentials of B.indica for the requirements of PRB: reducing the hydraulic conductivity and degrading the polycyclic aromatic hydrocarbons (PAHs). The hydraulic conductivity was estimated by rigid wall column test and finally the values were converted to the values of intrinsic permeability. The nutrient solution was passed through the biobarrier column to activate the bacterium and then leachate was in turn carried into the column to evaluate the durability of the biobarrier. Phenanthrene was selected as a representative substance of PAHs. The ability of degrading phenanthrene by B.indica was evaluated by two-phase partitioning bioreactor after estimating the possibility with two pretests: observing the colony formation and the optical density on glucose-free medium containing phenanthrene. With the results, B.indica produced large amount of strongly adhesive exopolysaccharides (EPS) and reduced several orders of magnitude of the hydraulic conductivity after 2 weeks of cultivation. Furthermore, about 1000mg/1 of phenanthrene could be degraded by B.indica in the two-phase partitioning bioreactor. In conclusion, the application of the bacterium, B.indica, was found to have a potential role of a PRB to retain and remove contaminants in porous media.

• Korean Journal of Soil Science and Fertilizer
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• v.6 no.2
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• pp.83-88
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• 1973

The newly devised column set is better than the conventional method with centrifuge, suction filter instruments for saturating of the salt and washing out the excess of salt for C. E. C. determination in soils. 1. The new method has a high significance with one suction filter set. 2. The new method deminishes the time and effort of analysis by one third. It can analyze many samples at a time. 3. It is able to analyze without expensive instruments (e. g. vaccum pump, shaker, suction apparatus and centrifuge).

• Geomechanics and Engineering
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• v.33 no.3
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• pp.243-259
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• 2023

Turkey is one of the most important earthquake regions in Europe. This region has been exposed to many earthquakes of different magnitudes from past to present. It is of great importance to determine the dynamic properties of the soils for structures to be built in earthquake zones. In order to minimize the damages that may occur, the behavior of the soils under repeated loads should be known and taken into consideration in the design. In this study, 4 different point borings were taken near active fault lines in the North Anatolian fault zone (NAFZ). In order to determine the dynamic parameters of soils, both dynamic triaxial (TRX) and resonant column (RC) tests were carried out on undisturbed samples at every 5 m. As a result of the experiments, V_s and G_max values were obtained from the field and differences were determined. The dynamic behavior of the soil was examined at varying depths with the comparison of reference models in the literature and compatible results were obtained. Finally, the behavior at the transition region is highlighted. As a result, three shear modulus and dumping ratio models have been proposed for clay soils to be used in different soil conditions.

• Archives of Pharmacal Research
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• v.17 no.6
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• pp.424-427
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• 1994

An acinomycin complex isolated from culture broth of a soil microorganism, SNUS 9305-011 has been examined by High performance liquid chromatography (HPLC). From the analysis of the fractions obtained by column chromatography of the ethyl acetate extract, three actinomycin components are confimed . The HPLC analysis is carried out with a CN-bonded nucleosil column. Comparison of the retention times of the components with those of actinomycin D, C complex, $X_{o{\beta}$, and V and suggests that they are different actinomycins. FBA mass spectra fo the coponents also shows different molecular ions from those of standards and other reported actionbmycins. The present work has demonstrated that actinomycin components can be separated by a CN-bonded HPLC column, and that ocmparison of their HPLC chormatograms with authentic smaples and information on their molecular ions can be successfully employed for indentification of actionmycins.

• Applied Biological Chemistry
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• v.40 no.2
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• pp.128-133
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• 1997

This study was conducted to evaluate the adsorption, desorption, leaching and degradation pattern of fungicide fluazinam in the soil environment under the laboratory conditions. The mode of isothermal adsorption of fluazinam in soil was coincident with the Freundlich equation. The adsorption amount of fluazinam was much higher on soils containing organic matter than on soils oxidized with hydrogen peroxide. The presence of organic matter, humic acid or fulvic acid, increased the adsorption amount of fluazinam on soils. The Freundlich constant K was much higher in soil added with humic acid than in soil added with fulvic acid. The desorption ratio of fluazinam adsorbed to soil was increased by removal of organic matter. In leaching experiment using soil column, the fluazinam applied on the soil surface was not moved down to the bottom of soil and was not detected in leachate water. The degradation of fluazinam was faster in Soil I with rich organic matter than Soil II with poor organic matter, in non-sterilized soil than sterilized soil, and in flooded soil than unflooded soil.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.2
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• pp.190-198
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• 2008

In this stduy, the column experiments were carried out assuming the soil was contaminated by leakage of gasoline containing MTBE from USTs and pipes around gas stations. Then, characteristics of MTBE transport in the soil were investigated using CXTFIT program. The column experiments with different soil properties, moisture content, organic matter content and flow rate were carried out. Some parameters(D, R, $\beta$, $\omega$) used in two-site non-equilibrium adsorption model were obtained from measuring the MTBE concentration in injection-liquid and in effluent and using CXTFIT program. In addition, The characteristics of MTBE transport in the soil was found using BTCs and obtained parameters. Consequently, the advection decreased as the increase of the content of fine particle and organic, while the MTBE transport by advection was enhanced as increasing flow rate and moisture content.

• Journal of Soil and Groundwater Environment
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• v.11 no.5
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• pp.51-58
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• 2006

In this study, uptake and toxicity of disel (TPH) by poplar specie, $P.\;nigra{\times}P.\;maximowiczii$ were assessed in laboratory soil column experiments. Poplar cuttings were grown for 2 months and exposed to various concentration (0, 200, 500, 1000, 2000 mg/kg) of disel for a period of 60 days. For disel removal experiments, disel was effectively removed in the range of lower concentration. but, the removal rate of disel was rapidly decreased as increasing initial disel concentrations. For the this reason, toxicity effetcs were evaluated by measuring in poplar cutting mass variation and monitoring transpiration. Exposure on higher disel concentration resulted in decrease of biomass and transpiration accompanied by chlorosis and abscission, indicating toxic effect of disel on the poplar tree. And also, we have observed that both removal efficiency of disel and the microbial activity were higher at the bottom of the soil column. It was suggested that the plant formed the root zone at contaminated soil, stimulated microbial activity by plant root exudates, and played an important role in enhanced biodegradation of disel.

• Microbiology and Biotechnology Letters
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• v.21 no.6
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• pp.600-608
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• 1993

About 1, 300 strains isolated from soil were evaluated for acyl-CoA:cholesterol acyltransferase (ACAT) inhibition activity. About 4.0% of actinomycetes and 3.6% of fungi showed greater than 50% inhibition activity, respectively. However, none of the isolated bacteria exhibited inhibition activity more than 50%. Among them, one Streptomyces sp. A-3 showed a higher ACAT inhibition activity in culture broth. Isolation of the ACAT inhibitor (AI-3) was achieved by Amberlite XAD-7 column, silica-gel column, Sephadex LH-20 gel-filtration and reverse phase HPLC.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.67-70
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• 2002

Remediation of groundwater contaminated with chlorinated organics, nitro aromatics, and heavy metals using zero valent iron (ZVI) filings has paid considerable attention in recent years. When the contaminants of high concentration leaked abundantly in subsurface environment, permeable reactive barrier technology using iron filing is taken a long time for the remediation of contaminated groundwater, The problem of contaminant shock is able to be solved using surfactant (hexadecyltrimethylammonium, HDTMA) modified bentonite (SMB) as immobilizing material. Therefore, the purpose of this research was to develop the combined remediation technology using conventional permeable reactive and immobilizing barrier for the enhanced decontamination of chlorinated compounds. Four column experiments were conducted to assess the performance of the mixed reactive materials with Ottawa sand, iron filing, and HDTMA-bentonite for trichloroethylene (TCE) removal under controlled groundwater flow conditions. TCE reduction rates with sand/iron filing/HDTMA-bentonite were highest among four column due to dechlorination of TCE by iron filing and sorption of TCE by SMB.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.257-260
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• 2002

The main purpose of this research is to find suitable treatment methods of wastewater effluent for artificial recharge. For this purpose, we search the effluent quality of wastewater treatment plant and possibility of additional filtration process. Particles ranged 2 ~ 5 ${\mu}{\textrm}{m}$ and 15~20 ${\mu}{\textrm}{m}$ in "T" WWTP(Waste Water Treatment Plant) effluent were relatively dominant. In dual-media filtration system operation, head-loss development of column 1 was about two times faster than column 2, and head-loss development within 5 cm from surface was very important factor in operation, Conclusively, for the stable filtration and running time of 1.5~2 day, influent turbidity must keep 5 NTU or below, and filtration system must operated at 280 m/day or below. After filtration of WWTP effluent, water quality reached satisfactory level. This water has potential of agricultural reusing, flushing water in building, recharging water to river or stream at dry season and artificial recharge of ground water.und water.