• The Journal of Engineering Geology
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• v.28 no.2
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• pp.207-215
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• 2018

Almost all countries of the world have recently made great efforts to reduce green-house gases to alleviate the global warming threatening human survival, because a huge amount of carbon dioxide as one of the main green-house gases has been emitted from the combustion processes of fossil fuels such as coal and oil. $CO_2$ capture and storage (CCS) technology is a representative method to diminish the green-house gases, and actively investigated by many countries. This study focuses on the design and construction of a high pressure $CO_2$ injection facility to store it to underground, which is the first $CO_2$ injection in Korea following the steps of the $CO_2$ capture from large $CO_2$ emission sources and transportation to the sea. Injection tests of $CO_2$ on the platform on the sea were carried out in Yeongil Bay of Pohang city in the early 2017. Thus, we were able to perceive the necessary operating conditions of the injection facility, injection characteristic, and knowhow of the injection facility. The results obtained from the injection test shall be utilized for facility upgrades and scale-ups.

• Journal of the Korea institute for structural maintenance and inspection
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• v.17 no.4
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• pp.57-65
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• 2013

The development of the oil refining industry has resulted in an annual 120 million tons of sulphur, which is a by-product of the desulphurization process. To exploit this abundance, the applications of sulphur must be expanded. as excellent durability of reuse of leftover sulphur which has high potential for utilization in construction materials, the study is actively in progress. Meanwhile, there has been active research on semi-rigid pavements that draw on the strengths and overcome the weaknesses of asphalt and concrete pavements. Acrylate is used to prevent cracking but involves a high cost, thus, an alternative material is required. As such, this study presents methods on the reuse of leftover sulphur and examines the engineering performance of grout containing sulfur polymer emulsion (SPE) for use in semi-rigid pavements. Our analysis shows that grout in which 30% of acrylate is replaced with SPE has superior properties in terms of time of flow and strength compared to regular grout. However, performance declined when more than 50% of acrylate was replaced by SPE, indicating that the optimum replacement level is 30%. Through SEM analysis, we found that grout with utra harding cement in this study at three hours had similar hydration properties to that of Type 1 Ordinary Portland Cement (OPC) at seven days, and maintained the properties regardless of grout containing SPE. OPC and grout with a replacement level of 30% displayed similar levels of chloride invasion resistance, whereas grout without SPE was far less resistant. Within the scope of this paper, the optimum replacement level of acrylate with SPE was found to be 30% in consideration of various properties such as time of flow, strength, and chloride invasion resistance.

• Journal of the Korean Institute of Gas
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• v.23 no.6
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• pp.25-32
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• 2019

In many mass-consumption gas facilities, natural gas is not supplied through the pipeline of the gas corporation. LNG is supplied from the gas corporation through the tank lorry to be vaporized. In order to prevent human or property damage due to gas leakage at these facilities, a study was conducted to analyze the concentration of odorant injected at the initial and consumption points. An analysis was performed to confirm the change in odorant concentration according to the pipe position in the gas facility when a constant flow rate flowed. For this study the gas samples were taken with aluminium cylinders(4.5 L) which were created a vacuum at the pressure regulator in which the odorants was injected and the points using the gas. Odorant levels of the samples were analyzed by Gas chromatography(Main Body : Agilent 7890A, Detector : ANTEC 7090).We suggest that the small facilities using LNG need to make the management system by the types of facilities for maintaining the odorization system.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.217.2-217.2
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• 2010

자연 상태에서의 가스하이드레이트의 존재는 물의 빙점보다 높은 온도에서 가스 수송관이 막히는 사고가 관내에 생성된 하이드레이트에 의한 것으로 규명된 이후영구동토지역이나 심해저에 부존되어 있는 막대한 매장량으로 인해 매우 활발한 연구가 최근에 진행되고 있다. 가스하이드레이트는 수분의 량에 비해 대량의 가스를 함유하므로 인위적인 가스하이드레이트를 제조하기 위하여 여러 가지 연구 중 하이드레이트 반응을 촉진하는 촉진제(promoter)와 생성을 억제하는 억제제(inhibitor)를 찾는 연구가 활발히 이루어지고 있다. 계면활성제와 고분자물질이 이들의 다양한 첨가제로 현제 사용되고 있다. 이러한 연구에서 메탄가스하이드레이트 형성에 영향을 미치는 대상물질로 선택한 DME(Dimethane Ether)는 산소 함유율이 34.8wt%인 함산소연료로 최근 신에너지로 부상하고 있으며, 해외 가스전 개발과 맞물려서 상용화단계에 들어와 있다. DME의 물리화학적인 특성으로는 상온의 온도에서 약5기압의 압력으로 액화 시킬 수 있다. 마취성이 강한 디에틸에테르와는 달리 마취성이 없을 뿐만 아니라 인체에 무해한 무색기체로 세탄가가 60가까이되어 경유(세탄가 55) 대체연료로 내연기관의 실증사업이 진행되고 있다. 이러한 특성을 갖고 있는 DME가 메탄가스 하이드레이트 생성에는 어떤 영향을 미치는지를 본 연구에서는 실험을 통해서 분석을 수행하였다. 실험과정에는 세 단계로 구분하여 진행하였는데 첫 번째 단계에서는 메탄가스만으로 하이드레이트 생성조건을 실험분석하였고, 두 번째 단계에서는 DME가스를 먼저 주입한후 동일 온도에서 메탄가스를 주입시켜 하이드레이트 생성 압력을 실험측정하였다. 마지막 단계에서는 DME가스를 약 두 배 정도 많이 주입한 후 동일 온도에서 메탄가스를 주입하여 하이드레이트 생성 압력을 측정하였디. 이러한 단계별 과정을 다소 온화한 $-5^{\circ}C{\sim}4^{\circ}C$의 온도 범위에서 반복적으로 수행하였다. 실험결과에서는 메탄만의 하이드레이트 형성보다 빙점($0^{\circ}C$) 이하의 온도 범위에서는 DME가 메탄하이드레이트 형성에 촉진제 역할을 하였고, 빙점 이상의 온도에서는 억제제의 역할을 하는 것으로 측정되었다. 또한 첨가된 DME의 양에 따라 촉진제의 역할과 억제제의 역할에 확연한 차이를 보였다. 추후 실험에서는 좀더 넓은 농도, 온도 및 압력범위에서 재현성 실험을 추가로 수행할 것도 제안한다.

• Journal of radiological science and technology
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• v.30 no.3
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• pp.281-287
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• 2007

Contrast media may cause tissue injury by extravasation during intravenous automated injection during CT examination. Here, we present a study in which contrast media extravasation was detected and localized in the neck and thorax by three-dimensional(3D) CT data reformation. The CT studies of the extavasation site were performed using a 3D software program with four different display techniques axial, multi planar reformation(MPR), maximum intensity projection(MIP), and volume rendering displays are currently available for reconstructing MDCT data. 3D image reconstructions provide accurate views of high-resolution imaging. This paper introduces extravasation with the MDCT and 3D reformation findings of contrast media extravasation in neck ant thorax. The followed injection of the external jugular vein into an existing intravenous catheter and a large volume of extravasation was demonstrated on by 3D MDCT.

• Journal of Korean Society of Forest Science
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• v.49 no.1
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• pp.6-10
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• 1980

The witches' broom disease of Paulownia tomentosa (Thunb.) Steud with which mycoplasmalike organisms are associated is widespread throughout Korea and poses serious threat to the cultivation of paulownia. Attempt was made to investigate the feasibility of field control of the disease with oxytetracycline hydrochloride (OTC). A total of 84 paulownia trees (6 year-old, DBH: 10-15cm) exhibiting severe symptoms of witches' broom were selected and treated during March to September. Solution of 1-10g of OTC dissolved in 0.1­2.0 of water was transfused into infected trees with gravity flow method from a dark-brown colored plastic reservoir (11 volume) through plastic tubes (1.2m long) connected to 2-4 holes (5 mm in diameter and 4-5cm in depth) bored in the basal part of the tree trunks (Fig. 1 and 2). Of 60 diseased paulownia trees injected with 2g of OTC in 0.1-2.0l of water during May to September, 1979, 58 trees resulted in complete remission of symptom development and resumption of healthy new growth at least up to September, 1980 when the last observation of the effect of OTC treatment for this experiment was made. The rest of two trees were dead probably due to too severe infection. Of 24 paulownia trees treated in March and April, 1979 complete remission of symptom development was obtained with 8 trees, and nine trees were partially prevented from symptom development in the following season. The remaining 7 trees were dead due to failure in uptake of OTC and partly because the trees were in too far advanced stage of infection. Application of highly concentrated solution of 2g of OTC dissolved in 0.1-0.2l of water per tree was just as effective as the 2g/1-2l treatment. Injection of 2g/1-2l required 3-4 days while treatment of 2g/0.1-0.2l reduced the time for injecting one tree down to less than 24 hrs. The result of this experiment demonstrates that basal trunk injection of 2g OTC/0.1-0.2l/tree is feasible for field control of paulownia witches' broom, provided that tree injection is performed in actively growing season (May-September) and at the initial stage of disease development.

• Korean Journal of Food Science and Technology
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• v.36 no.3
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• pp.518-521
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• 2004

Ginseng saponin was isolated from panax ginseng root using high-speed countercurrent chromatography (HSCCC). Preliminary studies were performed to optimize physical properties of two-phase solvent system and operating parameters including rotation speed of column, elution mode of mobile phase, and flow rate. Two-phase solvent system for isolation of ginseng saponins was composed of chloroform, water, and methanol as blending solvent. Chloroform-aqueous methanol (4:6) systems with various concentration of methanol in water were evaluated for retention of stationary phase in column. Retention of stationary phase decreased with increasing flow rate in tail-to-head elution mode using upper phase as mobile phase and head-to-tail elution mode using lower phase as mobile phase. Latter mode produced high retention at flow rate of 5 mL/min. Optimum conditions for isolation of saponin were chloroform/methanol/water (40/39/21) solvent system; mobile phase, of lower organic layer, flow rate, of 5 mL/min, head to tail elution mode, rotation speed, of 800 rpm, and sample injection, of $200{\mu}L$, Recovery yield of ginseng saponin from panax ginseng root extract by HSCCC was 63.6%, and the purity of HSCCC fractions was verified by TLC.

• Journal of the Korean Society for Marine Environment & Energy
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• v.3 no.1
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• pp.62-69
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• 2000

The study was performed to apply the algae removal system to coagulation-filtration process for minimize the damage to screen interruption of water treatment plants and died of fish by algae bloom on freshwater. Sample used Nokdong river water and Alkalinity, turbidity, chlorophyll-a and pH measured using Jar test and drum filter for coagulation-filtration process to determine optimum coagulation condition. A jar test apparatus and laboratory reactor were used in this study. The highest removal efficiency was observed when condition of flocculation time, coagulant dosage, drum filter rpm and chlorophyll-a concentration were to be 5min, 5mg/ℓ, 3rpm and 90㎍/ℓ, respectively. The average removal efficiencies measured of chlorophyll-a and turbidity using Alum were 50～60% and 30～50%, respectively. PAC was more effective than Alum in removal chlorophyll-a about 20%.

• Journal of the Korean GEO-environmental Society
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• v.13 no.10
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• pp.63-68
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• 2012

This study was performed to determine optimum conditions of batch type cultivation of Isochrysis galbana cultivated under various wavelengths of light emitting dioes (LEDs). Among LEDs used in the cultivation, white LED was found to be the most effective light source, and light intensity of 3,000Lux resulted in the most effective for the cultivation of Isochyrysis galbana. Comparison with common light source, fluorescent light, showed less effective than that with white LED. Four different air flow rates were tested to overcome shading effects due to denser cell concentration in the solution. In results, cell growth rates and maximum cell concentrations were similar regardless of air flow rates. Three times greater cell concentrations, however, were observed when air was applied.

• Clinical and Experimental Pediatrics
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• v.50 no.12
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• pp.1225-1230
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• 2007

Purpose : Multiple transfusions in patients with chronic anemia can result in excessive iron deposition in tissues and organs. Effective iron chelation therapy in chronically transfused patients can only be achieved when iron chelators remove sufficient amounts of iron equivalent to those accumulated in the body from transfusions, thus leading to maintain body iron load at a non-toxic level. This study was retrospectively carried out to investigate the effect of intravenous iron chelation therapy with deferoxamine in patients who have received multiple transfusions. Methods : From March 2005 to January 2007, 15 patients who have received multiple transfusions were included in this study. Transfusion dependent patients were defined as those receiving >1 packed red blood cell (RBC) units/month for at least 6 months. They received intravenous deferoxamine for 7 days (10-30 mg/kg/day, 24 hour continuous infusions). Before and after deferoxamine infusions and 3 months later, we compared serum iron, TIBC, and ferritin in transfusion dependent patients and transfusion independent patients. Results : There were 6 males and 9 females and their age range was 5.6-21.3 (median 8.3) years. Transfusion dependent patients were 7 and 8 were transfusion independent states after stem cell transplantation or chemotherapy. There was no significant change in ferritin level after deferoxamine treatment for the transfusion dependent patients but significant falling of ferritin level was observed for the transfusion independent patients 3 months later compared with baseline ferritin level (P=0.046). Some adverse events were observed but symptoms were mild and tolerable. Conclusion : Seven days of intravenous deferoxamine was safe and effective in transfusion independent patients. In transfusion dependent patients, chelation therapy should be maintained, in order to minimize or prevent iron accumulation and storage in the tissues.