• Korean Chemical Engineering Research
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• v.52 no.1
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• pp.92-97
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• 2014

Perchlorate ($ClO_4^-$) is an emerging contaminant of soil/groundwater and surface water. $ClO_4^-$ has been shown to inhibit iodide uptake into the thyroid gland and cause a reduction in thyroid hormone production. $ClO_4^-$ is highly soluble and very stable in water. Biodegradation by $ClO_4^-$-reducing bacteria (PRB) is considered the most important factor in natural attenuation of $ClO_4^-$. Rivers in an industrial complex have potential to be contaminated with $ClO_4^-$ discharged from point or non-point sources. In this study, water samples were taken from the rivers running through the Gumi industrial complexes and used for batch test to analyze $ClO_4^-$-degradation potential of river microorganisms. The results of 83-h batch culture showed that $ClO_4^-$-removal efficiency of all samples was 0.77% or less without addition of an external electron ($e^-$) donor. However $ClO_4^-$-removal efficiency was higher when an $e^-$ donor (acetate, thiosulfate, $S^0$, or $F^0$) was added into the batch culture, showing up to 100% removal efficiency. The removal efficiency was various depending on type of $e^-$ donor and site of sampling. When acetate was used as an $e^-$ donor, the highest $ClO_4^-$-removal efficiency was observed among the $e^-$ donors used in this study, suggesting that activity of heterotrophic PRB was dominant. The results of this study provide basic information on natural attenuation of $ClO_4^-$ by river microorganisms. The information can be useful to prepare a strategy to enhance efficiency of $ClO_4^-$ biodegradation for in situ bioremediation.

• 보존과학연구
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• s.33
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• pp.125-148
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• 2012

The Octagonal nine storied pagoda of Woljeongsa Temple consists mainly of granite with the rockforming minerals quartz, plagioclase, microcline, and biotite. The surface of the stone stupa is light brown that has been discolored by the rust from the metal ornament and aids. The surface of the stylobate and roof stone is colonized by biological contaminants. Therefore, a comprehensive deterioration diagnosis was carried out in this study, and conservation treatment was conducted. It was proven that the $Fe^{2+}$ yield increases depending on the count of poultice used with oxalic acid, but the $Mg^{2+}$, $Al^{3+}$, and $Ca^{2+}$ yields were marginal following the preliminary test. Therefore, the use of poultice is an effective way of removing the rust, and only marginally influences the rock. The biological contaminants were removed through dry cleaning, and the soil located under the contaminants was removed through wet cleaning. Based on this, the dry and wet cleaning of all the biological contaminants, and the use of poultice with oxalic acid, were done to remove the rust. For the conservation treatment of the metal ornament, the rust was removed through physical cleaning, and anticorrosion treatment was performed on the iron ornament using Renaissance wax and copper ornament by BTA.

• Korean Journal of Weed Science
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• v.17 no.4
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• pp.390-399
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• 1997

This experiment was conducted to introduce PAT (phosphinothricin acetyltransferase, non-selective herbicide bialaphos resistant gene) gene into potato (Solanum tuberosum. cv. Desiree). Optimal shoot regeneration from leaf discs and stem segments was obtained in MS medium supplemented with 0.1 mg/L IBA and 0.5 mg/L BA, and the frequency of shoot regeneration was 54% in left discs and 46% in stem segments. In this condition, leaf discs and stem segments of potato were co-cultivated with A. tumefaciens MP90 which contained binary vector with GUS: :NPTII gene and PAT gene. Transgenic shoots were regenerated from leaf and stem-derived calli on selection medium with 100mg/L kanamycin. The 100${\mu}M$ acetosyringone treatment during the co-cultivation highly enhanced(4 times than the control) the shoot regeneration on selection medium. When the putative transgenic plants were transferred to medium with 10mg/L basta, all of them were survived. After PCR. GUS test, and Southern blot analysis of the survived plant, we confirmed that the gene was stably integrated into the potato genome and expressed. After the transgenic plants were transplanted in soil, and the transgenic plants were sprayed with the herbicide basta (300ml/10a), the transgenic plants remained green but control plants were died.

• Korean Journal of Weed Science
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• v.15 no.3
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• pp.188-196
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• 1995

Blackgrass and water foxtail are troublesome weeds in a cultivation area of cereals. To know whether water foxtail could substitute for blackgrass as a plant material of screening for the discovery and development of new cereal herbicides, they were compared in a greenhouse and a growth chamber with respect to initial growth characteristics and responses to various herbicides. Blackgrass had a higher germination rate at lower temperature and a higher growth rate at higher temperature as compared to water foxtail. In addition, blackgrass was less sensitive to long day than water foxtail. These results suggest that blackgrass grows better in a cultivation area in spring than water foxtail. As compared to water foxtail, blackgrass showed shightly susceptible responses to herbicides when they were applied to soil surface at one day after seeding. However, the responses to the herbicides of blackgrass and water foxtail were similar with a foliar application of the herbicides at 3 or 4 leaf stage of the plant. Since there were no considerable differences in the herbicidal responses of the two plant species, water foxtail could substitute for blackgrass as a plant material for a primary herbicide screening. When water foxtail was used in a post-emergence screening test, seeding amount of 0.1g/$350cm^2$ and postemergence application of herbicides at 3 to 5 leaf stage were found to be appropriate on the view of alleviating screening efforts in a greenhouse.

• Journal of Life Science
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• v.18 no.1
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• pp.84-90
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• 2008

Bacterial colonies which were able to oxidize the manganese were isolated from six soil samples in Byungchon area. Among them, one bacterial strain was selected for this study based on its high manganese oxidation activity. This selected bacterial strain was identified as Pseudomonas sp. MN5 through physiological-biochemical test and analysis of its 16s rRNA sequence. This selected bacterial strain was able to utilize fructose and maltose, but they doesn't utilizing various carbohydrates as a sole carbon source. Pseudomonas sp. MN5 showed a very sensitive to antibiotics such as kanamycin, chloramphenicol, streptomycin and tetracycline, but a high resistance up to mg/ml unit to heavy metals such as lithium, manganese and barium. Optimal manganese oxidation condition of Pseudomonas sp. MN5 was pH 7.5 and manganese oxidation activity was inhibited by proteinase K and boiling treatment. The manganese oxidizing protein produced by Pseudomonas sp. MN5 was purified by ammonium sulfate precipitation, HiTrap Q FF anion exchange chromatography and G3000sw $_{XL}$ gel filtration chromatography. By sodium dodecyl sulfate polyacrylamide gel electrophoresis, three manganese oxidizing protein with estimated molecular weights of 15 kDa, 46.7 kDa and 63.5 kDa were detected. Also, it was estimated that manganese oxidizing protein produced by Pseudomonas sp. MN5 were a kind of porin proteins through internal sequence and N-terminal sequence analysis.

• Journal of Wetlands Research
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• v.22 no.4
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• pp.312-320
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• 2020

Various LIDs with natural water circulation function are applied to reduce urban environmental problems and environmental impact of development projects. However, excessive Infiltration and evaporation of LID facilities dry the LID internal soil, thus reducing plant and microbial activity and reducing environmental re duction ability. The purpose of this study was to develop a real-time measurement system with complex sensors to derive the management plan of LID facilities. The test of measurable sensors and Internet of Things (IoT) application was conducted in artificial wetlands shaped in acrylic boxes. The applied sensors were intended to be built at a low cost considering the distributed LID and were based on Arduino and Raspberry Pi, which are relatively inexpensive and commercialized. In addition, the goal was to develop complex sensor measurements to analyze the current state o f LID facilities and the effects of maintenance and abnormal weather conditions. Sensors are required to measure wind direction, wind speed, rainfall, carbon dioxide, Micro-dust, temperature and humidity, acidity, and location information in real time. Data collection devices, storage server programs, and operation programs for PC and mobile devices were developed to collect, transmit and check the results of measured data from applied sensors. The measurements obtained through each sensor are passed through the Wifi module to the management server and stored on the database server in real time. Analysis of the four-month measurement result values conducted in this study confirmed the stability and applicability of ICT technology application to LID facilities. Real-time measured values are found to be able to utilize big data to evaluate the functions of LID facilities and derive maintenance measures.

• The Journal of Korean Medicine
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• v.23 no.1
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• pp.67-82
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• 2002

Objectives: In recent years, extensive focus has been laid on adulteration of herbal medicine with heavy metals. This may be mainly due to soil contamination by environmental pollution. The objective of this study is to identify the contents of various heavy metals in the blood from Ohjeok-san (Wuji-san) Decoction (OD) treated-rats. Methods: For this study, 13 kinds of metals including essential and heavy metals, i.e. A1, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se and Zn were analyzed by a slight modification of EP A methods and the following results are obtained. Results: 1. There was no significant difference between the OD-treated groups and control group in liver, kidney, bone, brain and weight, especially no significant difference at the 5th and 10th days in weight and the amount of food intake. 2. The amount of each metal analyzed in the blood were as follows; A1: 2.3~3.07 mg/l, As: 2.90~3.66 mg/l, Cd: 0~0.001 mg/l, Co: 0~0.01 mg/l, Cr: 0.40~043 mg/l, Cu: 0.93~1.88 mg/l, Fe: 414.35~464.46 mg/l, Hg: 0.01 mg/l, Mn: 0.10~0.17 mg/l, Ni: 0.01 mg/l, Pb: 0.03~012 mg/l, Se: 0.73 mg/l, Zn: 3.41~4.13 mg/l by groups, respectively. In control and experimental group, Experimental I and other experimental II, III, IV, and V groups, there were no significant differences. 3. The amount of non-toxic metals (A1, Co, Cu, Fe, Mn, Se, Zn) were $64.1{\pm}7.71{\;}mg/l$ in the control group and 60.70~67.58 mg/l in the experimental groups I, II, III, IV and V. The amount of Toxic metals (As, Cd, Cr, Ag, Pb) were $0.68{\pm}0.21{\;}mg/l$ in the control group and 0.57 ~ 0.66mg/l in the experimental groups. The total amount of metals were 32.35 mg/l in the control group and 30.48~34.12 mg/l in the test groups I, II, III, IV and V, respectively. Conclusions: There was no significant difference of metal concentration in the blood from the OD-treated-rats compared to those of the control group even if higher dosage (1~8 times the dosage for a person) of OD was administered. This may be mainly due to a decoction treatment which contains only supernatants filtered from the herb-mass after boiling. This indicates the legal limitation for metal concentration in herbal medicine must be applied according to different treatment methods of herbal medicine.

• Korean Journal of Agricultural and Forest Meteorology
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• v.1 no.1
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• pp.12-19
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• 1999

CERES-rice, a rice growth simulation model, was used in conjunction with daily weather data to figure out the spatial variation of the phenology and yields of paddy rice at 168 rice cultivation zone units(CZU) of Kyunggi Province in 1997. Two sets of cultivar specific coefficients, which represent early and mid-season maturing varieties, were derived from field experiments conducted at two crop experiment stations. The minimum data set to run the model for each CZU (daily maximum and minimum temperature, solar irradiance, and rainfall) was obtained by spatial averaging of existing 'Digital Map of Korean Climate'(Shin et al., 1999). Soil characteristics and management information at each CZU were available from the Rural Development Administration. According to a preliminary test using 5 to 9 years field data, trends of the phasic development(heading and physiological maturity), which were obtained from the model adjusted for these coefficients, were in good agreement with the observed data. However, the simulated inter-annual variation was somewhat greater than the reported variation. Rough rice yields of the early maturing cultivar calculated by the model were comparable with the reported data in terms of both absolute value and inter -annual variation. But those of the mid season cultivar showed overestimation. After running the simulation model runs with 1997 weather data for 168 CZU's, rough rice yields of the 168 CZU's calculated by the model were aggregated into corresponding 33 counties by acreage-weighting to facilitate direct comparison with the reported statistics from the Ministry of Agriculture and Forestry. The simulation results were good at 22 out of the 26 counties with reportedly increasing yield trend with respect to the past 9 years average.

• The Korean Journal of Pesticide Science
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• v.7 no.2
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• pp.149-154
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• 2003

Potato blackleg disease caused by Erwinia carotovora subsp. atroseptica has been a serious problem in Korea. It was previously reported that four mixtures [streptomycin (9.3 ppm) + copper oxide (171.6 ppm)/copper hydroxide (146.3 ppm), streptomycin sulfate (7.0 ppm)+copper oxide (171.6ppm)/copper hydroxide (146.3 ppm)] were effective for the control of E. carotovora subsp. atroseptica. in in vitro test. Using those four mixtures and two antibiotics [streptomycin (81.4 ppm) and streptomycin sulfate (61.3 ppm)], the effectiveness of control for E. carotovora subsp. atroseptica. was conducted in the field. Two antibiotics showed over 60% of control efficacy under different soil conditions, while mixtures of two antibiotics with copper compounds did not show any control effects on the infected seed potato. Two mixtures [streptomycin (27.9 ppm)+copper hydroxide (438.9 ppm), streptomycin sulfate (21.0 ppm) + copper oxide (514.8 ppm)] were effective in the control of potato blackleg disease on the infected potato plants under different climate conditions.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.2
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• pp.130-137
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• 2005

This research programme include investigation of the adsorption behavior of heavy metals and VOCs by Pyrolysis char for using landfill cover material. The volatile potions in the sludge gasified during the pyrolysis period and gave birth to porosity throughout the matrix. The result of the ad/desorption experiment of nitrogen to find out the formation of some pore by the gasification of the volatile matter, we can certify that the pyrolysis char($14.56\;m^2/g$) has increased twice more than the organic wasted sludge($6.68\;m^2/g$) in specific surface area. The pyrolysis char has the adsorption characteristic of medium type of Type II and V in BDDT classification, and showed a little micro pore. In the adsorption experiment of ethylbenzene and toluene, as a result of applying the Freundlich adsorption isotherms, the pyrolysis char was higher in the adsorptivity of ethylbenzene and toluene than the granite and the organic wasted sludge. The results of the heavy metal adsorption test for the char indicated that it had some ability of adsorption. It is suggest that pyrolysis char has some advantages for utilizing as landfill covers because the pyrolysis char can adsorb/absorb hazardous substances from the landfill sites and inhibit the ground water and soil contamination.