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        검색결과 477

        461.
        2002.12 KCI 등재 서비스 종료(열람 제한)
        벤토나이트에 포함된 몬모릴로나이트의 층간에 Al산화물의 기둥(pillar)을 만든 Al-층간가교 점토를 합성하였다. 이 Al-층간가교점토에 대해 XRD, DTA, 화학분석 등을 실시하여 광물학적 특성을 검토하였으며, 그리고 이 가교점토에 대하여 Batch법의 흡착실험을 통하여 인산이온의 흡착성을 검토하였다. X-선 회절분석의 결과, Al-층간가교점토는 상온에서 층간격이 18.03 a으로 증가되어 나타났고, 550a가열에서도 약 17a을 나타내어 열적 안정성이 크며, 글리세롤에 의한 층간격의 팽윤은 매우 미약한 것으로 나타났다. 열분석 결과, 이 점토에는 pillar부분에 관련된 물의 탈수에 의한 것으로 보이는 270℃와 420℃의 특징적인 흡열반응이 나타났다. Al-층간가교 점토의 인산 이온에 대한 흡착실험의 결과, 몬모릴로나이트는 거의 흡착능력을 보이지 않는데 비하여 월등히 우수한 인산이온(PO43- /)성을 나타냈다. 시료 2 g에 용액 20 mL의 실험에서 300 mg/L 이하의 인산 농도에서는 거의 100%의 흡착효율을 나타냈다. 그리고 인산 이온에 흡착된 시료를 500℃로 가열한 후 재차 흡착실험을 행한 결과, 역시 매우 높은 흡착효율을 나타냈다. 따라서 Al-층간가교 점토의 인산 이온 흡착에 대한 재활용의 가능성이 큰 것으로 나타났다
        463.
        2002.04 KCI 등재 서비스 종료(열람 제한)
        Physico-chemical properties of the activated sludges(Suyoung and Changlim treatment plant), such as SVI(sludge volume index), absorbance, specific surface area, and specific resistance using Buchener funnel test were investigated with changing anaerobic storage time. This experimental condition was found that it was possible to estimate a linear relationship between their parameters such as specific surface area, specific resistance, and sludge volume index(SVI). The specific surface area and the specific resistance to filtration of the activated sludges of Suyoung and Changlim treatment plant were found as 123.6~136.6㎡/gDS and 41.5~44.9㎡/gDS(dry solid), and 1.09×1014 ~ 5.48×1014m/kg and 1.05×1014 ~ 2.48×1014m/kg, respectively. The results gave a good linear relationship between the specific surface area and the specific resistance, r=2.25×1012s-8.10×1013(R2=0.8885) at Suyoung treatment plant and r=1.26×1013s-4.75×1014(R2=0.8756) at Changlim treatment plant.
        464.
        2002.04 KCI 등재 서비스 종료(열람 제한)
        Optical microscope, SEM (Scanning Electron Microscopy) and fluorescent microscope were used for qualitative and morphological studies of the attached biomass on PE (polyethylene) substratum under anaerobic condition. It was shown by the observation of optical microscope that the initial attachment of biomass began in crevices of the surface of PE. The shape and structure of the attached biofilm could be observed by SEM photographs, but species of bacteria were and methanogens were not classified. A large number of methanogenic bacteria were identified on the surface of PE substratum by fluorescence under 480nm of radiation. It was estimated that methanogenic bacteria was also related to initial attachment of biomass under anaerobic condition.
        465.
        2002.03 KCI 등재 서비스 종료(열람 제한)
        The lab-scale anaerobic continuous reactor which was filled with the sludge of anaerobic digestion from Suyoung wastewater treatment plant was operated by feeding of various concentrations and flow rates. This experiment indicated that more than 6,870 mgCOD/L of substrate concentration was required to promote good metabolism and growth of anaerobic biomass. And increasing loading rate slowly was also required in order to treat substrate of higher concentration and higher loading rate. The substrate concentration of about 10,000 mgCOD/L was adequate to generate biogas efficiently. The pH was sharply decreased at the onset of higher loading rate, but the pH was restabilized soon at 8. During the experiment, the amount of the attached biomass was kept constant.
        466.
        2002.03 KCI 등재 서비스 종료(열람 제한)
        본 연구에서는 문헌조사를 통해 국내외 연안의 경관관리제도를 분석하였으며 먼저 연안의 경관관리에 앞서 가는 미국과 일본 연안도시에서 연안의 경관관리제도를 분석하였고 다음으로 우리나라 연안의 경관관리제도와 부산 연안의 경관관리제도의 현황과 문제점을 분석하였다. 이를 바탕으로 현행 관리체계 내에서 부산 연안의 경관관리제도 개선 방안을 제시하고 동시에 연안의 경관관리제도의 장기적인 개선 방향을 제시하였다. 본 연구결과 연안의 경관은 육지 경관과 바다 경관이 어우러져 구성되기 때문에 도시계획측면에서 보다는 연안관리차원에서 통합적인 관리가 필요하다 이를 위해 연안관리법을 기반으로 지역별로 연안경관관리조례를 만들어 구체적인 연안의 경관관리가 이루어져야 한다. 특히 연안의 경관 특성에 따라 연안경관관리지역을 설정하고 그 안에 경관보전지구, 경관회복지구, 경관계획지구를 두어 지구별로 관리하며 지역의 경관종합계획과 지구별 경관계획지침을 세워야 한다
        468.
        2001.04 KCI 등재 서비스 종료(열람 제한)
        Improvement of water quality and Investigation of bacterial characteristics have been conducted in a pilot plant using biological activated carbon (BAC) in water treatment process at the downstream of the Nakdong River. Most of water control parameters were highly improved after passing through BAC. Approximately 54% of dissolved organic carbon was removed in coal-based BAC process. Bacterial biomass and bacterial production appeared 9.8×108 CFU/g and 7.l㎎-C/㎥·hr in coal-based BAC, respectively. Predominant bacteria species grown in BAC were identified as Pseudomonas, Flavobacterium, Alcaligenes, Acinetobacter and Aeromonas species. Particularly Pseudomonas vesicularis was dominant in both coal-based and coconut-based BACs, while Pseudomonas cepacia was dominant in wood-based BAC.
        469.
        2000.08 KCI 등재 서비스 종료(열람 제한)
        Activated carbons were prepared from Korean coal by steam activation in this study. The variation of pore structure of the activated carbons were investigated according to different carbonization temperatures. Yield, surface area, pore volume and pore structure of this activated carbon were compared with those of activated carbon prepared without carbonization. The investigated carbonization temperature ranged from 700℃ to 1,000℃. Carbonization was carried out in nitrogen atmosphere for 70 minutes and activation was performed by steam at 950℃ for 210 minutes. Surface area and pore volume of the resulting activated carbons increased with carbonization temperature. Also pore volume increased by 20% compared to the activated carbon without carbonization. Especially, in mesopore region, the activated carbon carbonized at 900℃ had more pores by 60% than that of activated carbon carbonized at other temperature.
        470.
        2000.08 KCI 등재 서비스 종료(열람 제한)
        Activated carbons were prepared from Youngwall coal by steam activation in this study. The feasibility of the Youngwall coal to commercial activated carbon was examined. The variation of pore structures and the development of porosity in activated carbons were investigated by changing activation conditions in batch type apparatus. The values of BET surface area and adsorption capacity of iodine and methylene blue of the resulting activated carbons were obtained as high as 1,000㎡/g, 900㎎/g, 150㎖/g, respectively. Youngwall activated carbon prepared in this study showed much higher pore volume in pore diameter over l0Å than that of commercial reference activated carbon(Ningxia Taihua ZJ-15C) produced from China anthracite.
        475.
        1998.06 KCI 등재 서비스 종료(열람 제한)
        In order to develop of support media for biofilm reactor, physicochemical properties and attachability of surface of activated carbon, clay mineral, non-clay mineral, and waste mold sand were examined. Measured physicochemical properties of materials were surface roughness, mean particle size, surface area, hydrophobicity, and surface charge. At a tested materials, activated carbon was the best attachable material and microorganisms were attached 20.1 × 10^7 CFU/㎠ at surface, compared with diatomaceous earth which were attached of 9.2 × 10^7 CFU/㎠. In our research, surface area and hydrophobicity showed more influence than any other factor on attachment of microorganisms.
        476.
        1997.02 KCI 등재 서비스 종료(열람 제한)
        The objective of this study was to examine the transient response to hydraulic shocks in an inverse fluidized bed biofilm reactor(IFBBR) for the treatment of apartment sewage. The hydraulic shock experiments, when the system were reached at steady state with each HRT 12, 7, and 4hr, were conducted by changing twice HRT per day during 3days. The SCOD, SS, DO, and pH of the effluent stream were increased with hydraulic shock, but easily recovered to the steady state of pre-hydraulic shock condition. In spite of hydraulic shock, there were not much variation of biomass concentration, biofilm thickness, and biofilm dry density.
        477.
        1996.06 KCI 등재 서비스 종료(열람 제한)
        An inverse fluidized-bed biofilm reactor (IFBBR) was used for the treatment of highly-emulsified oily wastewater. When the concentration of biomass which was cultivated in the synthetic wastewater reached to 6000㎎/L, the oily wastewater was employed to the reactor with a input COD concentration range of 50㎎/L to 1900㎎/L. Virtually the IFBBR showed a high stability during the long operation period although some fluctuation was observed. The COD removal efficiency was maintained over 90% under the condition that organic loading rate should be controlled under the value of 1.5 ㎏COD/㎥/day, and F/M ratio is 1.0㎏COD/㎏VSS/day at 22℃ and HRT of 12 hrs. As increasing organic loading rates, the biomass concentration was decreased steadily with decreasing of biofilm dry density rather than biofilm thickness. Based on the experimental results, It was suggested that the decrease in biofilm dry density was caused by a loss of biomass inside the biofilm.
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