• Applied Chemistry for Engineering
• /
• v.9 no.3
• /
• pp.330-335
• /
• 1998

The objectives of this study are summarized with two. The one is to remove of $COD_{Cr}$, color and turbidity with coagulation and ozonation in nonbiodegradable landfill leachate, the other is to compare of water qualities with pre-ozonation and post-ozonation. The results are summarized as follows ; 1) 90 minutes ozonation with $75mgO_3/min$($4.5gO_3/hr$) was conducted at pH 4,7, 10 to remove $COD_{Cr}$. Removal efficiencies were investigated with 48.2%, 52.6%, and 62.3% respectively. As increasing pH, $COD_{Cr}$ removal efficiencies were increased, it was considered that hydroxyl radical($OH{\cdot}$) which strongly oxdize and nonselectively react with organic compounds, was rapidly produced by ozone self-decomposition at high pH. 2) Alum, ferric chloride and ferrous sulfate were used for coagulation as inorganic coagulant. Ferric chloride was investigated with optimal coagulant, and it removed $COD_{Cr}$ about 12.0% at pH5 and dosage of $2,000m{\ell}/{\ell}$. Cation(C-101P), anion(A-601P) and nonion(SC-050) were tested to remove organic pollutants in landfill leachate. Cation(C-101P) was investigated with the most effective organic coagulant, and removal efficiency of $COD_{Cr}$ was 19.8% at pH5 and dosage of $100m{\ell}/{\ell}$. 3) Color and turbidity were removed up to 88.6%, 97.0% at pH10, when contacted 90 minutes with ozone, respectively. These removal efficiencies were much higher than those of $COD_{Cr}$ and $COD_{Mn}$. It was considered that ozone could oxdize the triggering materials of color and turbidity selectively and preferentially. 4) $COD_{Cr}$, color and turbidity were more effectively removed with pre-ozonation than post-ozonation about 8%, 3.5% and 1% respectively. These results were well corresponed with other's studies that pre-ozonation will increase the effect of coagulation.

• Journal of the Korean Wood Science and Technology
• /
• v.44 no.1
• /
• pp.19-29
• /
• 2016

The purpose of this study is to analyze the combustion and thermal properties in order to establish baseline data for the fire safety evaluation of imported wood. The combustion properties such as heat release rate, total heat release, gas yield, and mass loss were analyzed by the method of cone calorimeter test according to KS F ISO 5660-1 and thermogravimetric analysis (TGA). Analyzed species are five kinds of species as Merbau, Mempening, Garo Garo, Malas, and Dillenia. The heat released rate values showed the highest value of Malas as $375.52kW/m^2$, and Dillenia showed the lowest value as $133.30kW/m^2$. The data values were confirmed in the following order: Malas > Mempening > Garo Garo > Merbau > Dillenia. In case of the total heat release, it was measured in the following order: Mempening > Malas > Garo Garo > Merbau > Dillenia. The gas analysis results were that Dillenia showed the highest value of 0.034. Also, Mempening and Malas showed the lowest at 0.020 in the $CO/CO_2$. Min of mass reduction was shown as 74.79% Sargent cherry, on the other hand, Malas had a 83.52%. It showed a correlation between and of the CO and $CO_2$ generation and combustion characteristics of wood. The thermal decomposition temperature of the wood in the TGA were as follow that Merbau $348.07^{\circ}C$, Mempening $367.57^{\circ}C$, Garo Garo $350.59^{\circ}C$, Malas $352.41^{\circ}C$, Dillenia $364.33^{\circ}C$. The aim of this study is to determine the combustion properties of imported wood according to ISO 5660-1. And, based on the results of this study, we would proceed with further research for improving the fire safety of wood for construction.

• Economic and Environmental Geology
• /
• v.38 no.6 s.175
• /
• pp.675-687
• /
• 2005

The rocks of the five storied stone pagoda in the Jeongrimsaji temple site are 149 materials in total with porphyritic biotite granodiorite. They include pegmatite veinlet, basic xenolith and evenly developed plagioclase porphyry. This stone pagoda has comparably small fracture and cracks which are farmed in the times of rock properties, but surface exfoliation and granular decomposition are in process actively since the rocks are generally weakened from the influence of air contaminants and acid rain. Structural instability of constituting rocks in the 4th roof materials are observed to occur from distortion and tilt. Such instability is judged to threat stability of the upper part of the stone pagoda. Also, chemical weathering is operating even more as the contaminants, ferro-manganese hydroxides eluted from water-rock interaction on the rock surface. Most of the rock surface is covered with yellowish brown, dark black and light gray contaminants, and especially occur in the lower part of the roof rocks on each floor. The roof underpinning rocks are severe in surface pigmentation from manganese hydroxides and light gray contaminants. The surface of rocks lives bacteria. algae, lichen, or moss and diverse productions in colors of light gray, dark Bray and dark green. Grayish white crustose lichen grows thick on the surface with darkly discolored by fungi and algae in the first stage on basement rocks, and weeds grows wild on the upper part of each roof rocks. This stone pagoda must closely observe the movements of the upper part rock materials through minute safety diagnosis and long term monitoring for structural stability. Especially since the surface discoloration of rocks and pigmentation of secondary contaminants are severe, establishment of general restoration and scientific conservation treatment are necessary through more detailed study for this stone pagoda.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.39 no.6
• /
• pp.796-804
• /
• 2010

This study was conducted to compare and analyze the qualitative property of MLT (mulberry leaf tea) and FMLT (fermented mulberry leaf tea) based on the antioxidant, anticancer activities of various extracts. When the antioxidant activity of MLT and FMLT extracts was evaluated, the electron donating activity was found to increase proportionally as the concentration of each extract increased. In addition, the extract of FMLT showed a higher electron donating activity than that of MLT. Furthermore, the ethanol extracts showed the highest electron donating ability. When the SOD activity was evaluated, it was also found to increase proportionally with the concentration of each extract. Furthermore, the SOD activity of the ethanol extract group was the highest, whereas the SOD like activities of both MLT and FMLT were similar. When nitrite decomposition was evaluated for each pH, the highest value was observed at pH 1.2. Finally, the nitrite deleting ability was the highest for the ethanol extracts. When each extract of MLT and FMLT was analyzed in vitro for anticancer effects, they were found to decrease the number of cancer cells proportionally as the concentration of extract increased for both HeLa cells and MCF-7 cells. Furthermore, FMLT was found to exert a greater inhibition of cancer cells than MLT. Among the extract groups, the ethanol extract induced the greatest inhibition of the development of cancer cells, and these effects were greater against MCF-7 cells than HeLa cells.

• Journal of Korean Society of Forest Science
• /
• v.105 no.3
• /
• pp.275-283
• /
• 2016

The objective of this study was to examine carbon dynamics with biomass, soil $CO_2$ efflux, litter and root decomposition after tree density control in young Pinus densiflora stands. The stands were established with 50% thinning, clear-cut, and control stands with three pseudo-replicated plots and a bare soil plot in 8-year-old Pinus densiflora nursery field. Monthly measurements were conducted from March 2012 to February 2014 and aboveground biomass and coarse-roots were estimated by derived allometric equations. Average diameter growth at root collar in control and thinned was 0.89 cm and 1.48 cm per year, respectively, and the diameter growth of control stand was significantly higher than that of thinned stands (p<0.05). Total biomass was estimated to 5.17, $4.85kg\;C\;m^{-2}$ per year in control and thinned, respectively. Annual soil $CO_2$ efflux in control, thinned, clear cut, and bare soil was 3.71, 3.90, 4.17, $4.56kg\;CO_2\;m^{-2}\;yr^{-1}$, respectively and removing trees significantly increased soil $CO_2$ efflux (p<0.05). Net Ecosystem Production (NEP) was 1.57, 1.36, -0.67, $-1.25kg\;C\;m^{-2}\;yr^{-1}$ in control, thinned, clear cut and bare soil in the young Pinus densiflora stands. NEP was significantly decreased by removing trees. Thinning increased diameter at root collar and carbon of individual tree and recovered 86% of carbon removed by thinning after one-year. In addition, soil $CO_2$ efflux increased and NEP increased by thinning. Results of this study, tree density control such as thinning increased the carbon storage and growth of the young Pinus densiflora stands.

• Korean Journal of Environmental Agriculture
• /
• v.32 no.3
• /
• pp.179-184
• /
• 2013

BACKGROUND: Accurate estimates of total direct $CH_4$ emissions from croplands on a country scale are important for global budgets of anthropogenic sources of $CH_4$ emissions and for the development of effective mitigation strategies. Methane production resulted by the anaerobic decomposition of organic compounds where $CO_2$ acts as inorganic electron acceptor. This process could be affected by the addition of rice straw, water management and rice variety itself. METHODS AND RESULTS: Rice (Oryza sativa L. Japonica type, var Samkwangbyeo) was cultivated in four plots: (1) Nitrogen-Phosphorus-Potassium (NPK) ($N-P_2O_5-K_2O$:90-45-57 kg/ha); (2) NPK plus 3 Mg/ha rice straw (RS3); (3) NPK plus 5 Mg/ha rice straw (RS5); (4) NPK plus 7 Mg/ha rice straw (RS7) for 3 years (2010-2012) and the rice straw incorporated in fall (Nov.) in Gyeonggi-do Hwaseong-si. Gas samples were collected using the closed static chamber which were installed in each treated plot of $152.9m^2$. According to application of 3, 5, 7 Mg/ha of rice straw, methane emission increased by 46, 101, 190%, respectively, compared to that of the NPK plot. CONCLUSION(S): We obtained a quantitative relationship between $CH_4$ emission and the amount of rice straw applied from rice fields which could be described by polynomial regression of order 2. The emission scaling factor estimated by the relationship were in the range of IPCC GPG (2000).

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.54 no.4
• /
• pp.351-356
• /
• 2009

Growth, milled rice yield and edible quality of rice in naturally reseeded Chinese milk vetch(CMV)-rice cropping system was compared with those in rice mono cropping on silty loam soil in Milyang from 2006-2008. Practicing natural reseeding technology recorded high CMV reseeding stand ranging from 565-805 plants $m^{-2}$ and resulting in the production of 13.0-17.0 kg N/10a from the CMV plant biomass which is greater than the recommendation rate of 9 kgN/10a. The plant height of rice plant grown in natural reseeding field is shorter at tillering stage but it was similar to the rice mono cropping at later stage. Dry matter production had similar trend to plant height. On the other hand, the leaf color in naturally reseeded CMV-rice cropping system was similar to the rice mono cropping up to panicle heading stage but it was high at mature stage, indicating that the nitrogen was provided by the CMV decomposition until later stage of rice. The yield components such as culm number $m^{-2}$ was greater and 1,000-brown rice weight was heavier than those of rice mono cropping but the ripened grain ratio was lower in naturally reseeded CMV-rice cropping system. Milled rice yield of naturally reseeded CMV-rice cropping system was similar to that of rice mono cropping. However, head rice percentage of milled rice was lower due to low ripened grain ratio. This result indicates that natural CMV reseeding technology can completely replace chemical fertilizer in CMV-rice cropping system.

• Korean Journal of Environmental Agriculture
• /
• v.18 no.4
• /
• pp.372-377
• /
• 1999

Objective of this research was to draw the basic criteria of the compost maturity evaluation, by assessing the stability of chemical and physical properties of the bark and piggery manure byproduct composts during the composting. Colors of the mature composts were black and dark brown for the bark and piggery manure by-product composts, respectively. Good earthy odor was detected for both by-product composts after approximately 40 days composting, by which odors of the original raw materials were disappeared. pH and EC of the mature bark: compost were stabilized at 6.5 and 1dS/m, respectively. The respective values for the piggery compost were stabilized at 7.2 and 6dS/m. Organic matter contents were decreased with time to be stabilized at about 60% at the end of composting. During composting, total N contents of the bark and piggery composts were maintained at $1.1{\sim}1.5%$, and $1.5{\sim}2.2%$, respectively. For both fertilizers, $NH_4-N$ contents were increased at the initial stage bur. decreased after the middle stages of decomposition, resulting in the increase of $NO_3-N$ contents. Total inorganic N contents were increased with time. C/N ratios of both mature composts were stabilized at $25{\sim}27$. CEC of the bark compost was increased logarithmically with time and that of mature compost was 87cmol(+)/㎏. CEC of the piggery manure compost was hyperbolic function with rime and reached at 70cmol(+)/㎏ at the mature stage. Crude fiber analysis indicated that relative contents of lignin were increased with composting by compensating for the decreases of cellulose and hemicellulose contents.

• Analytical Science and Technology
• /
• v.25 no.6
• /
• pp.483-491
• /
• 2012

This study is to investigate the issues on how to secure stability during the purification process for the production of recombinant protein A. The final recombinant protein A is produced by passing through the cation exchange column (SP) and the anion-exchange column (Q) during the production process, for which the samples produced by the step-by-step processes can be exposed to trouble in securing stable storage in case the next process cannot be taken within the proper time period. Accordingly, this study aims to evaluate the proper storage conditions and length of time when storing samples produced in the production process. That is, in this study, how to store fair samples, how long the storage period should be set up, and how to evaluate the security of its quality depending on time are dealt with. The items to be experimented with were enodotoxin, SDS-PAGE, HPLC purity and concentration. Experimental results showed that after passing the cation exchange column, when stored at $4^{\circ}C$ or room temperature, SDS-PAGE showed a major band, endotoxin is 5.0 Eu/mg or less, and concentration is on average of 8.21 to 8.24 mg/mL and RSD% 0.10~0.62%. In addition, HLPC purity showed somewhat stable results; at the HPLC purity 214 nm, the average is 99.24% to 99.37% and RSD% is 0.22~0.29%, while the average is 89.72% to 89.80% and RSD% 0.62~1.26% at 280 nm. On the contrary, after passing the anion exchange column, when stored at $4^{\circ}C$ or room temperature, SDS-PAGE revealed the major band, endotoxin is 0.5 Eu/mg or less, and concentration is on average of 5.59 mg/mL and RSD% 0.03~0.10%. when it comes to HLPC purity, the result showed that at the HPLC purity 214 nm, the average is 99.74% and RSD% is 0.10~0.11%, while the average is 96.16% to 96.85% and RSD% 0.72~1.13%. In conclusion, the stability of fair samples of recombinant protein A during the manufacturing process could be obtained without substance decomposition for 7~8 days at $4^{\circ}C$ or 20~21 days at room temperature.

• Korean Journal of Food Science and Technology
• /
• v.14 no.3
• /
• pp.197-202
• /
• 1982

Kinetic study for the thermal degradation of ginsenosides in ginseng extract was conducted. The results indicate that the thermal degradation followed first order kinetics and rate constants varied substantially depending on the types of ginsenosides and heat treatment temperatures. Activation energy calculated by Arrhenius plots ranged from 16.80 kcal/mole to 30.10 kcal/mole and $Q_{10}$ values ranged from 2.01 to 3.49. Correlation coefficients between the change of ginsenoside contents by thermal degradation and heat treatment temperature were $0.995{\sim}0.999$. The dependence on temperatures of the decomposition rate constant of total ginsenoside can be expressed as $k=4.574{\times}10^8$ exp(8898.8/T).