• Journal of the Korea Concrete Institute
• /
• v.26 no.2
• /
• pp.219-227
• /
• 2014

The purpose of this study is to investigate water purification properties of porous concrete by using effective microorganisms through the long-term continuous flow test. To solve the problems such as desorption of conventional microorganisms, in this study, tertiary treatment of the effective microorganisms identified by 16S rDNA sequence analysis was adopted per each step in the manufacturing process of porous concrete. And concentration for optimum continuous flow test and operation conditions through basic experiments according to retention time were investigated. Based on the experimental results, the porous concrete applying effective microorganisms showed no toxicity on the biological water quality and exhibited excellent removal efficiency than normal porous concrete. Therefore, contaminated water quality would be improved by treatment performance investigation of contaminants through long-term continuous flow test. If problems are complemented during the experiment process, it is expected to be able to reduce the non-point pollution sources flowing into river.

• Korean Journal of Environmental Agriculture
• /
• v.19 no.3
• /
• pp.223-227
• /
• 2000

Absorption of Cadmium(Cd) and Arsenic(As) by lettuce following to the change of polyamine content in lettuce were examined to find the effect of these elements on lettuce growth and on the basic resistance mechanism. As the contents of Cd and As were increased in soil, the contents of these elements were significantly increased in lettuce but lettuce growth was decreased. Sequential fractionation experiment of the Cd and As treated soil was shown that exchangeable, dilute acid extractable, and organically bound form, which were more mobile and phyto-available, of Cd were increased by 5.6, 42.9, and 56.7% during a growing season whereas 17.6, 25.0, and 24.1% were increased in case of As, respectively. Specially, the Cd content of leaves and roots in lettuce was positively correlated with exchangeable, dilute acid extractable, and residual form of Cd in the treated soil. However, the As content of roots in lettuce was positively correlated with all chemical forms of As in the treated soil. The contents of putrescine and cadaverine, a kind of polyamine, were also increased in lettuce as both elements were increased in soil.

• Korean Journal of Environmental Agriculture
• /
• v.19 no.4
• /
• pp.300-308
• /
• 2000

The degradation of herbicide $^{14}C-bifenox$ was studied in soils under anaerobic conditions. $^{14}C-bifenox$ was treated in silty loam and sandy loam soils, respectively at a rate of 2.1 mg/kg, and the soil was incubated under anaerobic conditions at $25^{\circ}C$ for 180 days. The mineralization, solvent extractable and non-extractable residues, degradation products of bifenox were investigated during the experiments. The relative amounts of $^{14}CO_2$ were 1.97 and 0.9% of applied $^{14}C$ in silty loam and sandy loam soils, respectively. The non-extractable residues of sandy loam soil increased dramatically up to 79.12% of applied $^{14}C$, and were higher than those of silt loam soil, suggesting physico-chemical properties and especially organic matter contributed to the difference of $^{14}C$ between two soils. The non-extractable residues were formed mainly humin fraction and increased with time. The major metabolites were nitrofen, 5-(2,4-dichlorophenoxy)-2-Nitrobenzoate, 2,4-dichlorophenoxy aniline and methyl 5-(2,4-dichlorophenoxy) anthranilate by GC/MS analysis. From the results of volatilization, mineralization and degradation of bifenox, bifenox was stable chemically and biologically in soil.

• Analytical Science and Technology
• /
• v.25 no.6
• /
• pp.350-363
• /
• 2012

To determine ionic species in snowpit samples using ion chromatography system, we described the performance of ion chromatography(IC) system, cleaning method of bottle, and interference by filtering procedure. The limit of detection, reproducibilities, and accuracies determined with BCR$^{(R)}$-408 were 0.01-0.26 ${\mu}g$/L, 0.4-17.4%, 4.5-12.0% for cations and 0.02-0.26 ${\mu}g/L$, 0.1-27.6%, 1.3-5.6% for anions, respectively. Lab blank test for sample bottle indicated that $CH_3CO_2{^-}$, $HCO_2{^-}$, and $NH_4{^+}$ can be easily contaminated in the lab environment. The positive interferences of $NO_3{^-}$ were partly attributed to the cleaning method of bottle. The filtering of melted snow sample should be carefully applied because it can positively affect the concentration levels of some ionic species. Finally, this method was applied to measure ionic species in snowpit samples from the upward area near NEEM camp and the uncertainties of measurement data of $F^-$ were also estimated.

• Korean Journal of Environmental Agriculture
• /
• v.8 no.1
• /
• pp.7-16
• /
• 1989

Application of steam distillation on the analysis of pesticide residue in soil, water and crops was studied using the nitrogen distillation apparatus. Most pesticides which were extracted by organic solvents could be analyzed by the steam distillation method. For instance, distillations of PCNB, ${\gamma}-BHC$, ${\alpha}-or$ ${\beta}-endosulfan$, IBP, diazinon, fenthion, fenitrothion, alachlor, butachlor, pretilachlor, metolachlor, pendimethalin, benthiocarb and molinate were possible, but not simazine, atrazine and nitrofen. The optimum volume of distillate for a sufficient extraction of pesticide varied according to kind of pesticide. In general, the volume needed was little for carbamate, but much more for organochlorine. When the definite amount of distillate was obtained and then the condenser was washed by acetone, the optimum volume of distillate was less. Using the steam distillation method, the amount of organic solvent needed for one extraction of pesticide from soil, water and vegetable was less than the conventional solvent extraction method, and the analytical procedure became simpler. The process of concentration and clean up was mostly unnecessary, although a ghost peak was apparent in the gas chromatogram according to the kind of materials distilled.

• Korean Journal of Environmental Agriculture
• /
• v.1 no.2
• /
• pp.116-122
• /
• 1982

Investigation on the water quality of Hwangguji River and experiment on the effects of nitrogen and soil improvements were carried out in the paddy field irrigated with polluted water of the river. The obtained results are as follows: 1) Amount of COD and $NH_4-N$ in water of the river were 54 ppm, 65 ppm, during the seeding time, and were 52 ppm, 512 ppm during the transplanting time respectively. Their concentrations were over the standard levels. It seemed that the water pollution was mainly caused by organic waste matters. 2) It seemed that the effective nitrogen level was $7{\sim}8$kg/10a in the paddy field irrigated with polluted water of the river. 3) The rice yields of potassium twice quantity application plot with N.P.K. fertilizer, the calcium application plot with N.P.K. fertilizer and the combined plot with potassium, wallarstonite, calcium and fresh straw, were increased 4, 5 and 8%, respectively, than that of the N.P.K. fertilizer standard level plot.

• Korean Journal of Environmental Agriculture
• /
• v.24 no.4
• /
• pp.319-325
• /
• 2005

Sediments of Mankyung and Dongjin river were examined on the physico-chemical properties and phosphorus fractionations. The content of total-P in sediment of Mankyung river ranged from 290.1 to 405.4 mg/kg (average = 363.4 mg/kg), while that in sediment of Dongjin river ranged from 304.1 to 431.7 mg/kg (average = 353.6 mg/kg). In both rivers, the total-P was highest in June to September. It is presumed that surficial sediment in arable land flowed into the rivers with rainfall-runoff. Phosphorus fractionations in Mankyung and Dongjin river were apatite-P 52.1% and 42.7%, residual-P 27.3% and 34.2%, nonapatite inorganic-P 18.1% and 22.5%, and adsorbed-P 0.6% and 0.6%, respectively. Adsorbed-P in sediment was the most scarcity fraction. It thus appears that adsorbed phosphorus was not effected in aquatic ecosystem. But nonapatite inorganic-P would be highly released under changes of redox condition and pH in aquatic ecosystem.

• Korean Journal of Soil Science and Fertilizer
• /
• v.41 no.6
• /
• pp.408-414
• /
• 2008

Importance of climate change and its impact on agriculture and environment has increased with the rise Green House Gases (GHGs) concentration in the atmosphere. To slow down the speed of climate change many efforts have been applied in industrial sectors to reduce GHGs emission and to enhance carbon storage. In agricultural sector, many researches have been performed on GHGs emission reduction, but few on the role of carbon sink. In this study, we investigated carbon balance and soil carbon storage in agricultural field in the barley-red pepper and barley-soybean cropping system. With the system for automatic measuring of carbon dioxide, net ecosystem production(NEP) was estimated to be $6.3ton\;CO_2\;ha-1$ for N-P-K chemical fertilizer treatment plot and $10.6ton\;CO_2\;ha^{-1}$ for N-P-K chemical fertilizer with swine manure treatment plot in the barley-soybean rotation cropping. In the barley-red pepper rotation cropping, it was $12.0ton\;CO_2\;ha^{-1}$ for N-P-K chemical fertilizer treatment plot and $13.2ton\;CO_2\;ha^{-1}$ for N-P-K chemical fertilizer with swine manure treatment plot. Soil carbon storage rate was estimated to be $0.7ton\;C\;ha^{-1}$ for the barley-soybean cropping system and $0.5ton\;C\;ha^{-1}$ for barley-pepper cropping system. In appeared that agricultural lands may contribute to the greenhouse effect as a potential carbon sink preserving carbon into soil.

• Conservation Science in Museum
• /
• v.13
• /
• pp.37-44
• /
• 2012

White crystals on 46 costumes excavated from Shim Su-Ryun(1534 - 1589)'s tomb were examined their characterization and distribution. In 36 of such samples, white crystals with different shape and hardness were found. The formation of crystals did not correlated with a kind and use of textiles. However, crystals were found in the back side than the front of costume, specially around the marks of shrouding dead body. White crystals from 7 textiles were investigated by EPMA, XRD, or FT-IR. The composition of white crystal was analysed by EPMA and the structure characterization of crystals was used by X-ray diffraction. FT-IR spectroscopy was applied to check if non-crystalline compounds were also present. Mg and P were detected as the main element of white crystals and these compounds were identified a struvite and newberyite, the inorganic mineral magnesium ammonium phosphates. Struvite precipitation are influenced by many factors including concentration of Mg²⁺, NH₄⁺, and PO₄^3- ions, pH, and temperatures. It is assumed that magnesium, phosphorous, ammonia, a base material of struvite comes from decomposition product of human body. Tomb covered with lime, a unique triple-structure in Joseon period offering the basic condition, an anaerobe in a coffin, and high magnesium concentration of outer coffin with lime can be inferred as important factor for precipitation of crystals.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.40 no.10
• /
• pp.1371-1377
• /
• 2011

This study was carried out to compare the antioxidative effects of various Nandina domestica fruits extracts. Organic fractions, including n-hexane, chloroform, ethyl acetate, and butanol fractions, were obtained from the water and ethanol extracts of N. domestica fruits. The phenolic compound content of the EE fraction was 922.22 mg/g. The flavonoid compound content was highest in the EB fraction (282.49 mg/g). The electron-donating ability was highest (93%) in the WA and EH fractions at 0.1 mg/mL. The SOD-like activity was showed the highest in the EA fraction (56.36%), and EH and EC both showed higher than 50% activity. The nitrite-scavenging ability of the EC fraction at 1.0 mg/mL under pH 1.2 conditions was 82.03%. The xanthine oxidase inhibitory activities of all the fractions, except WE, were higher than 90% at 0.5 mg/mL. The effect of tyrosinase inhibition was highest in the WE fraction (46.75%). These results show that the N. domestica fruits fractions contained high levels of polyphenol and flavonoid compounds, along with excellent antioxidative effects. This suggests that N. domestica fruits can be used as a functional material.