• Journal of Environmental Science International
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• 제4권3호
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• pp.117-117
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• 1995

An experimental research was conducted in order to study the treatability of municipal landfill leachate using a combined physio-chemical and biological treatment. The leachate was obtained from Nanjido landfill site in Seoul. Several sets of bench-scale sequencing batch reactor(SBR) and physic-chemical reactors were used as experimental apparatus. This experiment lasted for about 2 years. The results are as follows: 1. The characteristics of Nanjido landfill leachate were pH 7.4~8.2, BOD 79~450mg/L, COD 998~1460mg/L, $NH_3-N$ 1380~3412mg/L, 7-P 2.6~7.0mg/L, color 890~1992 unit, and heavy metals are a very small amount. 2. Either physio-chemical or biological treatment of Landfill leachate alone did not work well. So for the adequate treatment of leachate, it was necessary to deal with the physio-chemical pretreatment before biological treatment. And it was found that both electrolysis and ozone treatment are better pretreatments of leachate than others. 3. In this study, landfill leachate was effectively processed by two step : first by electrolysis pretreatment, and secondly by SBR treatment. Thus, the study showed considerable substrate removal of raw leachate, even though the rate of COD removal depended on HRT.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.585-588
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• 2007

As the distributed generation becomes more reliable and economically feasible, it is expected that a higher application of the distributed generation units would be interconnected to the existing grids. This new generation technology is linked to a large number of factors like economics and performance, safety and reliability, market regulations, environmental issues, or grid connection constrains. KEPCO (Korea Electric Power Corporation) is performing the project to develope the Distributed Micro Gas Turbine (MGT) technolgies by using Swine BIO-ENERGY. This paper describes the plans and strategies for the renewable energy of MGT on actual grid-connection under Korean situations. KEPCO also, has a research plan on bio-gas pretreatment system applicable to our domestic swine renewable resources and is performing concept design of pilot plant to test grid operation. In addition, this testing will be conducted in order to respond to a wide variety of needs for application and economic evaluation in the field of On-site generation.

• Journal of environmental and Sanitary engineering
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• 제11권1호
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• pp.45-55
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• 1996

An experimental research was conducted in order to study the combined treatment o of municipal landfill leachate and municipal sewage. The landfill leachate was that of Nanjido landfill site, and the municipal sewage was that of Chungnang municipal sewage treatment plant in Seoul. Several sets of bench~scale sequencing batch reactor(SBR) were used as e experimental apparatus. Specially investigated items in this experiment were the removal efficiency of substrate and the influence of treatment time. The experiment lasted for about 2 years. The result are as follows ; 1. The characteristics of leachate were pH 7.5~8.2, BOD 80~336mg/L, COD 908~1,460mg/L, NH3-N 1,409~2,330mg/L, T~P 2.7~7.lmg/L, Cl~3,540~4,085mg/L, a and heavy metals are a very small amount. And the characteristics of sewage were pH 6.9~7.3, BOD 78.4~129.3mg/L, COD 121.2~305.0mg/L, T~N 14.9~36.4mg/L, T-P 2.3~8.9mg/L. 2. The treatability of leachate alone was not treat well. So for the good treatment of leachate, it was necessary to deal with the pretreatment before bi이ogical treatment and a combined treatment of municipal sewage. 3. The various contents of the leachate were 5%, 10%, 30%, and 50%, and the removal efficiency of COD was 86.0%, 82.8%, 60.6%, and 31.7%. The maximum content of the leachate which could be sucessfully treated by SBR in the combined treatment was 10% of that of sewage. And the removal efficiency of COD increased n notably, as its treatment time increased. 4. The various contents of the electrolytic treated leachate were 5%, 10%, 30%, and 50%, and the removal efficiency of COD was 89.9%, 86.1%, 79.2%, and 69.8%. The maximum content of the leachate which could be sucessfully treated by SBR in the combined treatment was 30 % of that of sewage. And the removal efficiency of C COD increased notably, as its treatment time increased.

• Journal of Environmental Science International
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• 제2권2호
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• pp.145-152
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• 1993

An experimental research was conducted in order to study the treatability of leachate and a combined wastewater of municipal landfill leachate and municipal sewage. The landfill leachate was that of Nanjido landfill site, and the municipal sewage was obtained from Chungnang municipal sewage treatment plant of Seoul. Several sets of bench-scale sequencing batch reactor(SBR) were used as experimental apparatus. Specially investigated items in this experiment were the removal efficiency of substrate and the influence of the hydraulic retention time(HRT). The experiment lasted for about 8 months. The result are as follows ; 1) The characteristics of leachate were pH 7.4~8.1, BOD 280~450 mg/l, COD 1300 ~ 1350 mg/l, T-N 2021 ~2110 mg/1,7-P 2.7 ~3.2 mg/l, Cl-3540 ~4085 mg/l, and heavy metals are a very small amount. And the characteristics of sewage Ivere pH 6.9~7.3, BOD 78.4~129.3 mg/1, COD 121.2~305.0 mg/l, T-N 14.9~36.4 mg/l, T-P 1.3 ~5.9 mg/l. 2) The treatability of leachate alone was not treat well. So for the good treatment of leachate, it was necessary to deal with the pretreatment before biological treatment and a combined treatment of municipal serfage. 3) The various contents of the leachate were 5%, 10%, and 50% and the removal efficiency of COD was 86.0%, 82.8%, 60.6%, and 31.7%. The maximum content of the leachate which could be sucessfully treated by SBR in the combined treatment was 10% of that of sewage.

• Journal of the Korean Wood Science and Technology
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• 제51권2호
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• pp.133-144
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• 2023

Densification is an effective method for improving the physical and mechanical properties of low-density wood. However, the set-recovery of dimensions was found to be the problem of densified wood due to low fixation during the densification process. Alkali pretreatment before densification is thought to be a modification process to improve the dimensional stability of densified wood. In this research, the wood samples used were boiled in a 1.25 N sodium hydroxide (NaOH) solution at different times, followed by densification for 5 h at 100℃. The alkali pretreatment for 1, 3, and 5 h of boiling increased the dimensional stability of densified woods and anti-swelling efficiency values were 8.52%, 63.24%, and 48.94%, respectively. The boiling of wood in NaOH solution decreased the holocellulose content, as well as lignin to a lesser degree, and a lower crystallinity index was observed. The lower hydroxyl groups and a higher proportion of lignin in treated samples seem to have contributed to the high dimensional stability detected.

• Journal of Acupuncture Research
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• 제21권2호
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• pp.115-129
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• 2004

Objectives : To investigate the analgesic effect and its cholinergic mechanism of electroacupuncture(EA) in the rat model of collagen-induced arthritis(CIA). Methods : Immunization of male Sprague-Dawley rats with bovine typeII (CII) collagen emulsified in Freund's incomplete adjuvant, followed by a booster injection 14 days later, leads to development of arthritis in more than 70% of rats by 21 days postinjection. After three weeks of first immunization, EA stimulation(2 Hz, 0.07 mA, 0.3 ms) was delivered into Jogsamni($ST_{36}$) for 30 minutes. Analgesic effect was evaluated by tail flick latency(TFL). We compared the analgesic effect of EA with TFLs between pretreatment of normal saline and pretreatment of Atropine (1 mg/kg, intraperitoneal) and Neostigmine ($100{\mu}g/kg$, intraperitoneal) in CIA. Results : 1. TFLs were gradually decreased in CIA as increasing severity of arthritis. 2. Jogsamni($ST_{36}$) EA stimulation in CIA increased TFLs and the effect lasted for 60 minutes. 3. Increased TFLs with Jogsamni($ST_{36}$) EA stimulation were inhibited with pretreatment of atropine in CIA 4. Increased TFLs with Jogsamni($ST_{36}$) EA stimulation did not show an obvious synergistic effect with pretreatment of neostigmine in CIA. Conclusions: Jogsamni($ST_{36}$) EA showed analgesic effects in CIA. The analgesic effects of Jogsamni($ST_{36}$) EA were inhibited by atropine pretreatment and combined application of Jogsamni(ST36) EA and neostigmine did not show an synergistic effect. These observations suggest that intrinsic muscarinic cholinergic pathways represent an important modulating system in pain perception of inflammatory pain in CIA It is suggested that, the active mechanism of analgesic effect in EA may involve the release of acetylcholine in the spinal cord.

• Journal of the Korean Wood Science and Technology
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• 제39권1호
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• pp.95-103
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• 2011

We have investigated pretreatment of waste wood using milling refinery combined with poping method, which can save energy for pretreatment and enzyme loading for enzymatic hydrolysis. The chemical analysis of holocellulose of non and popping treated waste wood showed 65.9% and 58.8%, and the lignin, organic extracts and ash were increased by 3%, 4% and 0.7% after pretreatment, respectively. The reducing sugar yields of pretreated waste wood were increased four times more than non-pretreated one and the synergistic effect of cellulase and xylanase were evaluated compare with individual enzyme treatment. Especially, enzyme cocktail (cellulase 50 U and xylanase 50 U) treatment was very efficient in 1% substrate (50 mg). Also, glucose and xylose conversion rate of pretreated waste wood by GC analysis were 45.9% and 38.7%, respectively.

• Horticultural Science & Technology
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• 제16권3호
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• pp.374-376
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• 1998

Effects of traditional fumigation (methyl bromide; MB) and combined fumigation (methyl bromide/phosphide; $MB/PH_3$) on the disinfestation, and phytotoxicity and longevity of cut flowers (lily and rose) were investigated. Combined fumigation with low concentrations of $7/3g/m^3\;(MB/PH_3$) at $10^{\circ}C$ immediately after transportation from harvested place was found to be much more effective in disinfestation of aphid, mite, and thrips than fumigation with $MB\;48g/m^3$ only at $20^{\circ}C$ after simulated transportation for 2 days. Quality and longevity of cut flowers measured after fumigation were better in flowers treated by combined fumigation ($7/3g/m^3,\;MB/PH_3$) at $10^{\circ}C$ for 2.5-3 hrs, irrespective of pretreatment with pulsing solution immediately after transporation, even though phytotoxicity varied with cut flowers fumigated. On the other hand, fumigation with $MB\;48g/m^3$ only at $20^{\circ}C$ after simulated transportation for 2 days showed tendency of enhanced insect disinfestation, but caused phytotoxicity to both lily and rose, regardless of pretreatment and moreover, reduced the longevity of the cut flowers.

• Journal of Chest Surgery
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• 제32권11호
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• pp.998-1003
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• 1999

Background: Bovine pericardium treated with glutaraldehyde(GA) is one of the most popular prosthetic materials. However, its late calcific degeneration after implantation results in early failure of the prosthesis. Therefore, we investigated the effects of combined treatment with sodium dodecyl sulfate(SDS) and glutamate on calcific degeneration of GA treated bovine pericardium. Material and Method: Sixty square-shaped pieces of bovine pericardia were fixed in 0.625% GA solution with 4g/L MgCl2.6H2O as a control group (group 1). Sixty pieces pretreated with 1% SDS (group 2) and sixty pieces posttreated with 8% glutamate (group 3) were also fixed in the same GA solution. Sixty pieces pretreated with 1% SDS and posttrated with 8% glutamate were also fixed in the same GA solution (group 4). After 1 month of fixation, the pieces were implanted into the belly of sixty Sprague-Dawley rat subdermally and were extracted 1 month, 2 months and 3 months after the implantation. With an atomic absorption spectrophotometry, we measured the calcium amount deposited. Result: The calcium deposition in 1 month was 2.01$\pm$0.13 mg/g in group 1, 1.45$\pm$0.31 mg/g in group 2, 2.49$\pm$0.15 mg/g in group 3 and 0.75$\pm$0.27 mg/g in group 4. In 2 months, it was 3.57$\pm$0.15 mg/g in group 1, 0.98$\pm$0.30 mg/g in group 2, 3.46$\pm$0.12 mg/g in group 3, and 1.48$\pm$0.39 mg/g in group 4, and 5.45$\pm$0.42 mg/g in group 1, 2.43$\pm$0.53 mg/g in group 2, 4.20$\pm$0.55 mg/g in group 3, and 1.02$\pm$0.27 mg/g in group 4 in 3 months. The calcium depositions in group 2 and 4 were less than those of group 1 and 3 in 1 month 2, months, and 3 months(p<0.01). The calcium depositions in group 1, 2 and 3 increased with time. However, they remained unchanged in group 4, which was statistically significant(p<0.01). Conclusion: Pretreatment with SDS is effective in reducing calcification of GA treated bovine pericardium, and the combined method of pretreatment with SDS and posttreatment with glutamate was more effective than the other methods.

• Journal of Soil and Groundwater Environment
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• 제15권5호
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• pp.8-15
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• 2010

The purpose of this research is to check the validation of an auto-analysis method combined with aqua regia digestion apparatus for improvement of water distillation method used as a fluorine test of soil. Fluorine contents of CaO used in the pretreatment course of water distillation method were 120 mg/kg ~ 5,064 mg/kg at the blank test, which was exceeded up to maximum 12.5 times of the soil standard, so it was estimated due to a effect of fluorine existing as impurities of CaO. The recovery test of the same samples indicated that water distillation method and auto-analysis method were 134.5mg/kg and 161.7mg/kg respectively, the recovery ratio of the latter was 16.8% higher than the formal. The validation test of two methods satisfied the standard, but auto analysis method was excellent more than distillation method. Also, auto analysis method could save a analysis time up to maximum 4.7 times by comparison with water distillation method.