• Title/Summary/Keyword: 대기 시료

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Laboratory Measurements on the Uptake of Carbon Monoxide by Soils (토양의 일산화탄소 제거에 관한 연구)

  • Myung Ja Kim
    • Journal of the Korean Chemical Society
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    • v.27 no.1
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    • pp.31-37
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    • 1983
  • The consumption of atmospheric carbon monoxide by soil was measured under laboratory conditions in different types of soils. Laboratory experiments were performed with humus containing high proportion of organic matter, roadside soils, and humus and roadside soils previously exposed to high concentration of CO by reusing in the experiment. CO concentrations in the 18.2 l-reaction vessel were varied from 2,000 ppm to 24,000ppm to estimate the effectiveness of CO consumption at high level of CO. The uptake of CO by soil was measured by gas chromatography using a TCD detector. The control experiments conducted along with the soil experiments evidently indicated that the potting soil is responsible for CO consumption. Humus showed much higher CO uptake rates compared with the soil taken from roadside. The humus reused in the experiment showed somewhat higher rates(15%) of uptake than the fresh one. The soil's ability to remove CO from the test atmosphere reached a maximum near the CO concentration of 13,000 ppm in the range of $9,000~24,000ppm$. The addition of streptomycin did not influence the removal capacity of soil significantly, whereas 10% saline solution remarkably prevented CO uptake of the humus sample.

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A study of Stability of Emulsion Fuel (에멀젼 연료의 안정성에 대한 연구)

  • Kim, Moon-Chan
    • Journal of the Korean Applied Science and Technology
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    • v.37 no.5
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    • pp.1330-1343
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    • 2020
  • In this study, emulsion fuel which contained water of 10 ~ 20% was prepared mixed with water and MDO(Marine Diesel Oil) which largely used in near sea. Diffusion stability of emulsion fuel was measured. Diffusion stability was measured at 30℃, 45℃, and 60℃ for 10 days respectively. The stability of the emulsion fuel was stabilized in the order of MDO-10 > MDO-13 > MDO-16 > MDO-20 and it means that the stability of the emulsion fuel was found to be stable in the order of low water content. Meanwhile, an engine dynamo-meter was used to test whether the manufactured emulsion fuel was actually available in the engine. The emulsified MDO emulsion fuel could be used as fuel for ships. For samples with more than 16% water added emulsion fuel, smoke was reduced by more than 50% in the load area of more than 50%, and nitrogen oxides were reduced by 20%.

Characteristics of EMCs for Roof Runoff (강우시 지붕유출수의 EMCs 및 특성비교)

  • Hong, Jung Sun;Geronimo, Franz Kevin F.;Mercado, Jean Margaret R.;Kim, Lee-Hyung
    • Journal of Wetlands Research
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    • v.14 no.4
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    • pp.657-665
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    • 2012
  • The development projects distort the natural water circulation system and increase the non-point source pollution by changing the natural cover type. The low impact development (LID) techniques are considering as new development approach to decrease the ecological- and hydrological impacts from high imperviousness rate. The high imperviousness rate is because of the construction of building, parking lot and road for human activities. Knowing the basic characteristics of rood runoff can give the direction for setting up the water management strategy. The monitoring results show the pollutant EMCs of roof runoff are 3~13 times lower than EMCs of the road and parking lot. The pollutant sources from roof runoff are mainly from leafs, cigarette butts, atmospheric deposition and materials of the roof. The EMC is occurred around 15minutes later after starting runoff and more than 8 storm events are needed to have the average EMCs.

The Study of Luppe Smelting with Converting Dust and Slag (제강전로 더스트와 슬래그를 이용한 루페제련에 관한 연구)

  • 황용길;이상화;김재일;김연수
    • Resources Recycling
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    • v.7 no.2
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    • pp.39-45
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    • 1998
  • We smelted thc pellets made by mixing the distilled carbon from wlISte Lires, LD converter dust and slag with reduction process in the revcrberatory furnace. Thc obtained results are as follows 1) The removal mte of zinc appears above 97% after T reducing the pellets at $1300^{\circ}C$ for Ihr and the zinc content in the residue are 0.1~D.2%. 2) Under the mixing condition of 500 g LD dust. 150-200 g LD slag and 30-50 g distilled carbon of waste lires the removal raho of zinc shows above 95%, while t the 50-60% Fe remains in the residue. 3) After smelting at $1350^{\circ}C$ for 3hrs, the recovery ratio of pig iron reduced from lhe p pellets containing 15-20% LD slag and 4.1-7.2% distilled carbon of waste tires appears in the range of 89.3-92%. 4) Tbe c chemical composition of the recovered pig iron is 1.7%C, O.05%P, 0.05%S and balance Fe. 5) Tbe recovered dust from the d dust collcctor alter finishing the reduction rcaction appears as a crude zinc oxide conLaining 60% zinc.

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Chemical Forms and Release Potential of Heavy Metals from the Lime Treated Sediments (석회 처리에 의한 오염 퇴적물 내 중금속의 형태 변화 및 용출 가능성)

  • Park, Gil-Ok;Jun, Sang-Ho
    • Korean Journal of Ecology and Environment
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    • v.41 no.2
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    • pp.166-173
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    • 2008
  • Chemical forms and release potential of heavy metals were studied in the lime treated sediment of lake Chungcho. Chemical forms of heavy metals were analyzed using a sequential extraction method, and release potential of heavy metals was evaluated by the ratio of the content of labile forms to total metal one. Dominant form of Cd, Cu, Pb, and Zn in the untreated sediments was organic/sulfidic form that is stable in the reducing environment such as the bottom of Lake Chungcho. With liming of the sediment, the chemical forms of studied metals were greatly changed from organic/sulfidic form to adsorbed and reducible form, especially Cd and Cu to adsorbed and reducible form, but Pb and Zn to reducible form. It is believed that increase of unstable form of heavy metals in the sediments by liming was caused by the increase of pH of the pore water at the expense of organic/sulfidic form. Thus, we concluded that the liming approach currently used in the treatment of dredged sediments might cause the increase of labile form which is easily dissolved, and may increase the release of metals from the sediment into overlying water.

Monitoring and Analytical Techniques for the Discharged Radiocarbon from Nuclear Facility (핵시설로부터 발생되는 방사성탄소 분석기술 및 감시)

  • Chun, Sang-Ki;Kim, Nak-Bae;Kim, Kun-Han;Choi, Su-Young;Park, Chan-Jo;Lee, Joung-Dae;Shin, Jang-Sik
    • Analytical Science and Technology
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    • v.13 no.6
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    • pp.693-698
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    • 2000
  • The object of this series of experiments was aimed for the systematic and long-term radioactivity monitoring through indirect search of C-14 concentration level changes in the natural conditions around the operating nuclear facilities. The result of environmental radioactivity level through tree-ring analysis is increased after operating nuclear facilities and such a level can be proved to relate power generation closely. The measured result of ${\delta}^{13}C$ through the treatment of cellulose can be showed the level -30‰. This figure is very different from one which is measured the -17‰ of air sample by passive air sampling and -8‰ of air sample by active air sampling. And these differences can be assumed as isotope fractionation by photosynthesis, but the problem is more study as needed.

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A Fundamental Study on the Influence of Fresh Concrete Quality Properties due to the Cover of Concrete Mixer Truck (콘크리트 믹서 트럭 덮개의 유무가 콘크리트 품질 특성에 미치는 영향에 관한 기초연구)

  • Chae, Young-Suk;Lim, Byung-Hoon
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.14 no.6
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    • pp.198-204
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    • 2010
  • The cover of truck agitator give in a part to prevent the lower flowing of fresh concrete when the concrete are transported from the ready mixed concrete plant to the construction field. As a result of the question data, it show up a dirty image to the general civil society. Due to the above image, it is predicted to affect the image of the construction company, so we did the site experiment of the flowing, the amounts of air, the temperature change of concrete with the concrete left in the site, to find out the usefulness. Also, for the comparing with this, we got the result by doing the inner experiment with the same condition. As the result of the experiment, the cover of truck agitator affect little to the reduction of slump. The change of the air amount, regardless of the existence of cover, was not effected much in proper level until 60minutes. In addition, The compression strength was proper to the goal design strength until 90minutes regardless of the cover of truck agitator exist or not exist.

High Pressure Phase Transition Study of ${\alpha}$-cristobalite $GaPO_4$ (${\alpha}$-크리스토발라이트 구조의 $GaPO_4$에 대한 고압 상변이 연구)

  • Hwang, Gil-Chan;Kim, Young-Ho
    • Journal of the Mineralogical Society of Korea
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    • v.23 no.3
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    • pp.267-272
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    • 2010
  • High pressure x-ray diffraction patterns of ${\alpha}$-cristobalite gallium phosphate ($GaPO_4$) were acquired up to 8.9 GPa at room temperature using Mao-Bell type diamond anvil cell with high flux synchrotron radiation. Starting orthorhombic phase (phase-I) shows the splitting of peak which is possibly resulted from the pressure induced orientation disorder of the framework structure of tetrahedra. This is designated as phase-I'. This phase transforms to the orthorhombic high pressure phase-III between 2 and 3 GPa. Present phase transition sequence is not in accord with the recent high pressure X-ray diffraction results performed on the same starting sample (Ming et al., 2007). X-ray pattern of the unloaded sample to ambient pressure shows that the structure retains that of the high pressure phase prior to decompression.

Estimation of Tritium Concentration in the Environment based upon Global Tritium Cycling Model (글로벌 삼중수소 순환 모델을 이용한 삼중수소 환경 방사능 추정)

  • Choi, Heui-Joo;Lee, Han-Soo;Kang, Hee-Suk;Lee, Chang-Woo
    • Journal of Radiation Protection and Research
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    • v.28 no.1
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    • pp.1-8
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    • 2003
  • The periodic safety review of operational nuclear power plants requires that the plants should keep a well organized environmental monitoring program. The past records of environment monitoring data were analyzed. and the tritium concentrations of the samples in the surface and ground water around Kori site were measured. It was shown that the tritium concentrations around the Kori site were slightly higher than that of natural background. The change of background tritium concentration was estimated through a numerical modeling. Two different versions of 7 compartments model - the world and the northern hemisphere - defined in NCRP-62 were modeled for the global tritium cycling. The numerical solution of the model was obtained using a computer program, AMBER. The four cases of tritium source-terms into the atmosphere were considered. The results showed that the tritium concentration in the surface soil water was higher than that in sea water or surface stream water. Also, it was shown that the tritium produced by the interaction between cosmic rays and the gases were the major source of tritium, and the tritium produced by nuclear weapon test decreased considerably.

Removal of Phenol Loaded with Activated Carbon by Potentiostatic Method (정전위전해에 의한 활성탄에 함유된 페놀 제거)

  • 김성우;박승조
    • Resources Recycling
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    • v.10 no.4
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    • pp.18-23
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    • 2001
  • Air pollutants, phenol was generated in case of thermal regeneration of used activated carbon loaded with phenol and because of this problem, removal process of phenol were studied. Electrolytic oxidation of samples, used S.company granular activated carbon (WS-GAC), used C.company granular activated carbon (WC-GAC) and used L.company granular activated carbon (WL-GAC) loaded with phenol carried out by potentiostatic method in this study. In case of experiment was to come into operation in condition of samples containing 100 mg/g phenol, supporting electrolyte was 1.0% sodium chloride solution, Ti-Ir (10$\times$10$\textrm{cm}^2$) electrode and electrode distance was 2 cm, current density was $1.25 A/dm^2$, Obtained from the results of electrolytic oxidation experiments were not detected residual phenol. And then we knew about reaction time of electrolytic oxidation, current density, concentration of supporting electrolyte and electrode and electrode distance were 60 minutes, 1.25 A/dm$^2$, 1.0%, 2 cm.

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