• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.51-52
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• 2003

대기 중에서 HOx(OH, H $O_2$) 라디칼은 매우 중요한 산화제로, 대류권내 광화학 반응에 있어 그 역할이 핵심적이라 할 수 있다. 이러한 OH 라디칼의 정확한 농도를 측정하는 것은 대기의 산화능, 기후 변화 및 대기 중의 광화학 반응을 보다 정확히 이해하기 위해 매우 필요한 연구이다. 그러나 OH를 비롯한 HOx 라디컬의 농도 측정은 이들이 라디칼이기 때문에 매우 어려운 것이 사실이다. 즉, 이들은 대기 내에 존재하는 양이 절대적으로 적고 (OH: $10^{6}$molecules cm-$^3$, H $O_2$: $10^{8}$molecules cm-$^3$), 반응성이 커서 수명이 짧기 때문에 측정에 많은 어려움이 따른다. (중략)

• Journal of environmental and Sanitary engineering
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• v.10 no.3
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• pp.99-104
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• 1995

The objective of this study was to investigate the effect on denuclearization and decertification of flue gas by utilizing Mg( OH)$_{2}$ and NaOH as reagents in industrial boiler. We used packed absorber with Tellerette in all cases. And pH of circulation solution, rate of liquid per gas in absorber, COD concentration by pH variation in oxidation basin were inves- tigated. The following conclusions were obtained from experimental results: 1. Concerning running cost for reagents, Mg( OH)$_{2}$ reagent for treatment of flue gas was more economical than NaOH. 2. While Mg( OH )$_{2}$ and NaOH as absorbents were used, then the ratio of denuclearization was 96 and 97% respectively and nitrification was recorded 29 and 25% . 3. In this absorption tests the optimum condition for ratio of liquid per gas, pH and nonregenerable salt concentration of circulation solution were 3.6ℓ /Nm$^{3}$, 6.0, 0.5∼1.0% respectively, 4. Initial COD in oxidation basin was 800 ∼ 1,00099ut after adjusting to pH 7.0, COD of effluent water was less than 20ppm.

• Journal of Korean Society of Water and Wastewater
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• v.11 no.1
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• pp.53-63
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• 1997

The corrosion problems in water distribution system are reduced by decreasing the agressivity of drinking water which is evaluated by marble test and saturation indices(LSI or CCPP etc.). Marble test is a reliable method to determine the actual saturation condition of treated water. This study was done to determined the aggressivity of tap water and the effectiveness of $Ca(OH)_2$ and NaOH dosage for corrosion control. The drinking water in Seoul were evaluated by marble test and Langelier Index(LSI) and Calcium Carbonate Precipitation Potential(CCPP). The results indicated that the drinking water in Seoul were undersaturated as Calcium Carbonate($CaCO_3$). The LSI and CCPP of the water treated with $Ca(OH)_2$ were higher than that of water treated with NaOH. Therefore, to increase the Alkalinity and Calcium Hardness for corrosion control in water distribution system, $Ca(OH)_2$ is more effective than NaOH.

• The Journal of Korean Medicine
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• v.16 no.1 s.29
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• pp.451-467
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• 1995

In order to study on Bu-ja(Oh-du) toxicosis, the outhor investigated many documents. The results obtained were as follows: 1. Toxicosis of Bu-ja(Oh-du) arised mainly from carelessness in use. 2. In the symptoms of Bu-ja(Oh-du), Heart System(心系) symptom often came out. 3. The general and local paralysis, falling of blood pressure in Heart System(心系) symptom : vertigo, cramp in Liver System(肝系) symptom : nausea, vomiting in Spleen System (脾系) symptom : difficulty of breathing in Lung System(肺系) symptom : wasting disease in Kidney System (腎系) symptom frequently originated from toxicosis of Bu-ja(Oh-du). 4. In the detoification method, there are atropin injection, carrying out a gastric lavage, and supplying a liquid medicine from the western medicine : taking ginger-licorice root decoction, taking mung beans thick decoction and getting vomited with soaked cinnamon from the oriental medicine. And also keeping warm and oxygen inhalation were used to counteract poison. 5. A pregnant woman, heat of excess type(實熱), yang sydrome(陽證 )must not be taken Bu-ja(Oh-du).

• Journal of the Korean Ceramic Society
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• v.38 no.4
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• pp.319-324
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• 2001

본 연구에서는 NaOH로 첨착시킨 활성탄의 표면특성변화와 H$_2$S 흡착능을 고찰하였다. 첨착시약으로 사용된 NaOH 용액의 농도는 1~8N이며, 활성탄의 입자크기는 8$\times$30mesh가 적용되었다. 실험결과는 첨착율이 0.87~5.8% 범위 내에서 증가할수록 BET 표면적은 1050$m^2$/g에서 783$m^2$/g로 감소하며, 표면산도는 0.541meq/g-AC에서 0meq/g-AC으로 감소하고, pH는 9.56에서 10.86으로 증가하는 것으로 밝혀졌다. 또한 NaOH로 첨착시킨 활성탄의 H$_2$S 평형흡착능을 보임으로써 비첨착활성탄에 비해 2~3배 높은 수준을 나타냄을 알 수 있었다.

• Journal of the Korean Society of Combustion
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• v.8 no.1
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• pp.36-45
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• 2003

The subject of turbulent premixed flames has been focused by many researchers for a number of decades. Especially, Borghi suggested a magnificent diagram classifying turbulent combustion areas and Lipatnikov and Chomiak modified this diagram. Recently, experimental techniques have been developed so that we can use PIV for measuring 2D velocity field and apply OH PLIF techniques for obtaining flame locations. In present study, a new diagram is proposed using strain rates and OH signal intensity. Thus, simultaneous PIV and OH PLIF measurements are used for shear strain rates and flame locations, respectively. It is believed that the shear strain rates represent flow characteristics such as turbulence intensity and the OH intensity indicates the flame characteristics such as burning velocities.

• Journal of Astronomy and Space Sciences
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• v.12 no.2
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• pp.157-167
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• 1995

OH/IR stars are the most massive and youngest subclass in asymptotic giant branch stars which pass through sporadic superwind phases. We have modeled the dust envelopes around OH/IR stars with close attention to the evolution of the structure of the dust shells. We use various dust density distributions to take account the effect of the superwind due to the helium shell flash by adding a density increased region. Depending on the position and quality of the density increased region, the model results are different from the results with conventional density distribution. The new results fit the observations of some OH/IR stars better. Especially, the OH/IR stars with excessive 30-100$\mu$m emission can be better explained by the new results. The IR two-color diagrams comparing the results of the superwind models and IRAS observation of 95 OH/IR stars have been made. The new results can explain much wider regions on the IR two-color diagrams.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2005.10a
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• pp.335-340
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• 2005

• Journal of the Korean Ceramic Society
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• v.19 no.3
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• pp.223-228
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• 1982

For the preparation of ferroxidure BaO.5.5 $Fe_2O_3$ with high coercive force, the green and calcined coprecipitates, which were obtained by neutralizing the mixed salt solution $FeCl_2-BaCl_2$ and $FeCl_3-BaCl_2$ with alkali solution $NaOH-Na_2CO_3$, were investigated about the thermal reaction, crystal growth, and the magnetic properties of the sintered specimens. The very single-domain crystallites of Ba-ferrite with high coercive force are formed from the coprecipitate of amorphous $Fe(OH)_3$ and amorphous $BaCO_3$ at lower temperature than that of subnucleus crystalline $\delta$-FeOOH and amorphous $BaCO_3$.

• 한국가시화정보학회:학술대회논문집
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• 2004.11a
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• pp.102-103
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• 2004

Simultaneous CH and OH planar laser induced fluorescence(PLIF) and stereoscopic particle image velocimetry(PIV) measurements have been developed to investigate the local flame structure of turbulent premixed flames. The developed simultaneous two radical concentrations and three component velocity measurements on a two-dimensional plane was applied for relatively high Renolds number turbulent premixed flames in a swirl stabilized combustor. All measurements were conducted for methane-air premixed flames in the corrugated flamelets regime. Strong three-dimensional fluctuation implies that misunderstanding of the flame/turbulent interactions would be caused by the analysis of two-component velocity distribution in a cross section. Furthermore, comparisons of CH-OH PLIF and three-component velocity field show that the burned gases not always have high-speed velocity in relatively high Renolds number turbulent premixed flame.