• Journal of Environmental Science International
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• v.25 no.3
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• pp.439-446
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• 2016

Domestic sewerage treatment plant is operated by activated sludge method and its modified method by using microorganism. In most cases, a method of using microorganism is directly controlled by the operator based on individual judgment through factors of DO, pH and ORP. In addition, under aerobic condition in bioreactor, energy consumption including excessive air injection is learned to be somewhat plenty. In order to solve this problem, in most of the process, improvement of internal recycling and activated environmental factor of microorganism were researched extensively. However, as factors are changed depending on various conditions, it is not sufficient as an indicator of judgment. As such, a research on operation of bioreactor that measures metabolic change in short time by directly measuring activated condition of microorganism using NADH fluorometer is required in reality.It is considered that the method like this could supplement problem of energy consumption being occurred in the existing treatment method and operational optimization of bioreactor would be enabled by controlling optimal air volume. Therefore, in this study, in order to obtain optimal operational indicator of bioreactor, proper air volume control test was performed and through batch test and site evaluation, possibility of NADH sensor being utilized as operational control indicator of bioreactor is intended to be analyzed. In order to compare with measured value, DO, ORP that are operational control indicator of existing bioreactor were used. As MLSS concentration was increased through batch test, NADH value was increased and site evaluation also showed similar tendency to batch test. Resultantly, it could be confirmed that changing level of NADH fluorometer was a sensor that could measure bioreactor condition effectively and optimized scale of bioreactor is considered to be utilized.

• The Journal of Engineering Geology
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• v.30 no.2
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• pp.185-198
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• 2020

High-density rapid expansion material is a method that increases the solid volume of injection materials due to hydration and foam reactions at the same time as spraying. It is an effective method for securing ground stability, restoring subsidence, and loading during construction of structures. In this regard, through the mechanical experiments of injection materials, the stability of the foundation ground of the structure and the effect of increasing the endurance using site construction were analyzed. The results of the experiment showed that the unit weight of soil decreased by 10.5% after injection of the filling material, and the allowable support for the structure was deemed safe, and the subsidence by each section after ground improvement was determined to be safe at 2.28, 1.55 and 0.46 cm, respectively, with an acceptable subsidence of less than 5 cm. After the field test, five inclinometers were installed on the top floor of the target building to measure the displacement of the X and Y axes. As a result of the measurement, no displacement related to the phenomenon of inequality or subsidence cracks of the structure was measured for about 16 months (509 days) after construction. This can be judged to be a sufficient increase in the stability of the ground after the injection of rapid expansion.

• Journal of Korean Society on Water Environment
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• v.22 no.4
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• pp.590-598
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• 2006

In-situ Air sparging (IAS) is a groundwater remediation technique, in which organic contaminants volatilize into air form the saturated to vadose zone. This study was carried out to evaluate the effect of sludge and soil microbial community structure on air sparging of Total Petroleum Hydrocarbons (TPH) contaminated groundwater soils. In the laboratory, diesel (10,000 mg TPH/kg) contaminated saturated soil. The Air was injected in intermittent (Q=1500 mL/min, 10 minute injection and 10 minute idle) modes. For Terminal-Restriction Fragment Length Polymorphism (T-RFLP) analysis of eubacterial communities in sludge of wastewater treatment plants and soil of experiment site, the 16S rDNA was amplified by Polymerase Chain Reaction (PCR) from the sludge and the soil. The obtained 16S rDNA fragments were digested with Msp I and separated by electrophoresis gel. We found various sequence types for experiment with sludge soil samples that were closely related to Agrococcus, Flavobacterium, Thermoanaerobacter, Flexibacter and Shewanella, etc, in the clone library. The results of the present study suggests that T-RFLP method may be applied as a useful tool for the monitoring in the TPH contaminated soil the fate of microorganisms in natural microbial community.

• Journal of Korean Society on Water Environment
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• v.24 no.1
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• pp.19-29
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• 2008

Hot air sparging is a groundwater remediation technique, in which organic contaminants volatilized into hot air from the saturated to vadose zone. In the laboratory diesel (10,000 mg TPH/kg) was spiked in contaminated saturated aquifer soil. The hot air ($34.9{\pm}2.7^{\circ}C$) was injected in intermittent (Q=1,500 mL/min, 10 minute injection and 10 minute idle) modes. We performed microcosm tests using the groundwater samples to assess TPH reductive remediation activity. For Terminal-Restriction Fragment Length Polymorphism (T-RFLP) analysis of eubacterial communities in sludge of wastewater treatment plants and soil of experiment site, the 16S rDNA was amplified by Polymerase Chain Reaction (PCR) from the sludge and the soil. The obtained 16S rDNA fragments were digested with Msp I and separated by electrophoresis gel. We found various sequence types for hot air sparging experiment with sludge soil samples that were closely related to Bacillus (149 bp, Firmicutes), Methlobacterium (149 bp, Euryarchaeotes), Pseudomonas (492 bp, ${\gamma}$-Proteobacteria), etc., in the clone library. In this study we find that TPH-water was reduced to 78.9% of the initial value in this experiment aquifer. The results of the present study suggests that T-RFLP method may be applied as a useful tool for the monitoring in the TPH contaminated soil fate of microorganisms in natural microbial community.

• IMMUNE NETWORK
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• v.3 no.3
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• pp.211-218
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• 2003

Background: Vitamin C is an essential nutrient, taken as a daily supplement by many people. Recently, high-dose vitamin C is considered as a therapeutic regimen in some clinical situations. Until now, few studies have been done with the effects of high-dose vitamin C on the immune response. Methods: In this experiment, the effects of high-dose vitamin C on cell-mediated immune response in immunologically competent mice were evaluated. After intraperitoneal injection of 2.5, 5, or 10 mg/day of vitamin C for 10 days, delayed type hypersensitivity (DTH) was provoked against DNFB in the pinnae as a model for cell-mediated immune response. Severity of DTH reaction was evaluated as the thickness of pinnae, and the vitamin C levels were measured in the serum, liver, kidney, lung, pinnae, and splenocytes. Results: After challenge, the thickness increased at its peak on the $2^{nd}$ day in all groups. On the first day, the pinnae were thicker in the injected groups than in the control. On the contrary, the increment of the pinnae thickness was attenuated and the number of cells infiltrated in the site of DTH decreased proportionately to the amount of vitamin C administered from the second day on. With vitamin C exogenously given, the serum level peaked at 30 min after injection, and returned abruptly to its basal level without accumulation. However, it accumulated in the liver, kidney, and especially in the pinnae inflamed and splenopcytes, proportionately to the amount administered. Conclusion: Based on these results, it is suggested that, in one hand, exogenously administered high-dose vitamin C accumulated in the splenocytes and presumably changed the function of them resulting in the augmented cell-mediated immune response, as was revealed in the first day of DTH reaction. On the other hand, it seems likely that the vitamin C also showed anti-inflammatory effects.

• Journal of Soil and Groundwater Environment
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• v.15 no.4
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• pp.21-29
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• 2010

As the target area of this study, the coal mine site of Dongwon Sabuk mine.,ltd. is located in the remote mountainous region. To purify the acid mine water contaminated with heavy metals, a pilot-scale plant was built at the surrounded area of a mine shaft and operated to simulate active treatment system that could not only possibly setup the facility in a small available area, but also has a high efficiency. According to the various conditions of basin sequence, existence of sludge return, and lime injection position, six different types of treatment series were investigated in terms of treatment efficiency. As a result, the aluminum concentrations of the most effluents were in the range of 0.005~0.030 mg/L, which was too low to compare. The manganese concentration in the treated water were in the range of 3~9 mg/L, not following any regular trend. As found in the results of iron concentration, the case of addition of oxidation and sludge return steps showed higher efficiency than the others. As a standpoint of the installation of full-scale physicochemical treatment facility, the experimental results showed that the batch of oxidation and high density sludge return processes are existed and neutralization was followed by oxidation, had a stable treatment efficiency.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.4
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• pp.397-401
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• 2006

A laboratory study was conducted to evaluate the kinetics of oxidation of trichloroethylene(TCE) in groundwater by potassium permanganate($KMnO_4$). Consumption of permanganate by TCE and aquifer material was also evaluated to obtain an appropriate injection rate of $KMnO_4$. TCE degradation by $KMnO_4$ in the absence of aquifer material was effective with a pseudo-first order rate constant, $k_{obs}=5.24{\times}10^{-3}s^{-1}\;at\;KMnO_4=500mg/L$. TCE oxidation by $KMnO_4$ was found to be second order reaction and the rate constant, $k=0.65{\pm}0.08M^{-1}s^{-1}$. Meanwhile, aquifer materials from the field site were actively reacted with permanganate, resulting in the significant consumption of $KMnO_4$. It might be attributed to the existence of metal oxides in the aquifer materials.

• The Journal of Korean Medicine
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• v.22 no.2
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• pp.109-119
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• 2001

Objective : There are many reports that acupuncture has thermoregulatory effects on human and animals. To investigate the effect and mechanism of antipyretic action of acupuncture, we observed the body temperature and cytokine expressions in the hypothalamus of rats. Methods : Lipopolysaccharide (LPS, i.p., 2.5mg/kg) was injected to conscious rats (Sprague-Dawley, male, n=4l) to cause hyperthermia and simple needling (stainless steel, 0.25 mm o.d., 5 mm insertion for 10 sec with no manipulation) was performed bilaterally with the measurement of rectal temperature. Next, we sacrificed rats to remove brain and determined the level of mRNA for interleukin-6 (IL-6), $interleukin-1{\beta}{\;}(IL-1{\beta})$, interleukin-2 (IL-2) and $interferon-{\gamma}{\;}(IFN-{\gamma})$ in the hypothalamus by using reverse transcriptase-polymerase chain reaction (RT-PCR). Resul1s : Needling on forepaw (acupoint HT8) and needling on hindpaw (acupoint BL66 and acupoint LR2) significantly inhibited LPS-induced fever of rats (P<0.01, 10 min after treatment respectively), but same treatment on proximal tail (non-acupoint) did not cause any change on fever. The levels of IL-6 and $IL-1{\beta}$ mRNA in the hypothalamus was significantly enhanced by LPS-injection, while the level of IL-6 and $IL-1{\beta}$ mRNA was markedly reduced after treatment on BL66 (P<0.01). Treatment on forepaw reduced it slightly, but not significantly. Equivalent stimulation on proximal tail did not cause any changes. Conclusions : Our results indicate that acupuncture stimulation on various body parts has differential thermoregulatory effects on LPS-induced fever of rats with site-specificity. And, we suggest that its antipyretic action might be accompanied with the suppression of hypothalamic production of pro-inflammatory cytokine of immune system, IL-6 and $IL-1{\beta}$.

• Economic and Environmental Geology
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• v.45 no.6
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• pp.661-672
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• 2012

Lab scale experiments to investigate the dissolution reaction among supercritical $CO_2$-sandstone-groundwater by using sandstones from Gyeongsang basin were performed. High pressurized cell system (100 bar and $50^{\circ}C$) was designed to create supercritical $CO_2$ in the cell, simulating the sub-surface $CO_2$ storage site. The first-order dissolution coefficient ($k_d$) of the sandstone was calculated by measuring the change of the weight of thin section or the concentration of ions dissolved in groundwater at the reaction time intervals. For 30 days of the supercritical $CO_2$-sandstone-groundwater reaction, physical properties of sandstone cores in Gyeongsang basin were measured to investigate the effect of supercritical $CO_2$ on the sandstone. The weight change of sandstone cores was also measured to calculate the dissolution coefficient and the dissolution time of 1 g per unit area (1 $cm^2$) of each sandstone was quantitatively predicted. For the experiment using thin sections, mass of $Ca^{2+}$ and $Na^+$ dissolved in groundwater increased, suggesting that plagioclase and calcite of the sandstone would be significantly dissolved when it contacts with supercritical $CO_2$ and groundwater at $CO_2$ sequestration sites. 0.66% of the original thin sec-tion mass for the sandstone were dissolved after 30 days reaction. The average porosity for C sandstones was 8.183% and it increased to 8.789% after 30 days of the reaction. The average dry density, seismic velocity, and 1-D compression strength of sandstones decreased and these results were dependent on the porosity increase by the dissolution during the reaction. By using the first-order dissolution coefficient, the average time to dissolve 1 g of B and C sandstones per unit area (1 $cm^2$) was calculated as 1,532 years and 329 years, respectively. From results, it was investigated that the physical property change of sandstones at Gyeongsang basin would rapidly occur when the supercritical $CO_2$ was injected into $CO_2$ sequestration sites.

• Korean Chemical Engineering Research
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• v.47 no.5
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• pp.630-638
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• 2009

A computational fluid dynamics(CFD) model is developed and validated with on-site experiments for a urea-based SNCR(selective non-catalytic reduction) process to reduce the nitrogen oxides($NO_x$) in a municipal incinerator. The three-dimensional turbulent reacting flow CFD model having a seven global reaction mechanism under the condition of low CO concentration and 12% excess air and droplet evaporation is used for fluid dynamics simulation of the SNCR process installed in the incinerator. In this SNCR process, urea solution and atomizing air were injected into the secondary combustor, using one front nozzle and two side nozzles. The exit temperature($980^{\circ}C$) of simulation has the same value as in situ experiment one. The $NO_x$ reduction efficiencies of 57% and 59% are obtained from the experiment and CFD simulation, respectively at NSR=1.8(normalized stoichiometric ratio) for the equal flow rate ratio from the three nozzles. It is observed in the CFD simulations with varying the flowrate ratio of the three nozzles that the injection of a two times larger front nozzle flowrate than the side nozzle flowrate produces 8% higher $NO_x$ reduction efficiency than the injection of the equal ratio flowrate in each nozzle.