• Title, Summary, Keyword: microorganism

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A Study on the Properties of Microbial Cementation Soil for Engineering Applicability (미생물 고결토의 공학적 특성 연구)

  • Oh, Jong-Shin;Hwang, Soung-Won;Kang, Hee-Bog;Kang, Keon-Soo;Kim, Jong-Ryeol
    • Proceedings of the Korean Geotechical Society Conference
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    • pp.1332-1343
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    • 2008
  • The purpose of this study was to investigate the feasibility of using sedimentation calcium carbonate production based on microorganism activities in the strength manifestation of various soil conditions including ground. For analysis and comparison of microbial cementation soil's strength, unconfined compression test was executed by each content of soil(S), water(W), microorganism(B), microorganism and deposit (BF), microorganism, admixture and deposit(BCF) at specimen. The result, the strength of SB(soil+microorganism) and SBF(soil+microorganism+deposit) increased about 8%, 15% than SW(soil+water). Also, initial strength increased. But the strength of SBC(soil+microorganism+admixture) and SBCF(soil+microorganism+deposit+admixture) increased about 71%, 115% than SW(soil+water). The results of the SEM analysis, leading to the formation of an adhesive substance layers at the surface and resulting in firm particle configuration. The XRD examination of the sediment resulting from the reaction between the microorganism and the deposit control agent confirmed the presence of a type of calcium carbonate ($CaCo_3$) vaterite, which affects soil strength formation, as well as sodium silicate, silicides and so forth. This indicates that microorganism plays an important role in the production of carbonate ($CaCo_3$), sodium silicate and silicides. It affects to revelation of ground strength.

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Effects of Compost Mixed with Microorganism Compost Fermented on the Seedlings Growth of Tomato and Red Pepper (미생물부숙퇴비의 상토 혼합처리가 토마토, 고추 유묘의 생장에 미치는 영향)

  • 김홍기;서범석;정순주
    • Korean Journal of Organic Agriculture
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    • v.5 no.2
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    • pp.125-140
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    • 1997
  • This experiment was carried out to investigate the effects of compost mixed with microorganism compost fermented for the production of high quality plug seedlings of tomato and red pepper. The results are summarized as follows. As a result of compost analysis, EC value was increased with increment of microorganism compost supplemented but lowered gradually in the late period of seedlings growth, pH value of microorganism compost fermented was 9.3 which is strong alkalinity. In the plot of 30 percent of microorganism compost fermented early growth of tomato seedlings was better in terms of plant height, leaf area and total dry weight. However, early growth of red pepper seedlings was shown in the plot of supplemented with 20 percent of microorganism compost fermented. The higher the mixing rate over 60 percent of micrroganism compost fermented to the soil used retarded the seedlings growth regardless of tomato and red pepper.

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Sorption and Degradation of Benzene by Hydrogen Peroxide and Microorganism in a Sandy Soil (사질토양에서의 과산화수소 및 미생물에 의한 Benzene의 흡착 및 분해)

  • 백두성;박춘화;김동주
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • pp.101-107
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    • 2000
  • Column tests using KCl and Benzene as tracers were conducted for four different cases: 1) no hydrogen peroxide and no microorganism; 2) hydrogen peroxide only; 3) microorganism only; 4) hydrogen and microorganism to investigate the sorption and degradation characteristics of Benzene. The observed BTCs of KCl and Benzene in all cases showed that the arrival times of the peaks of both tracers coincided well but the peak concentration of Benzene was much lower than that of KCl. This result reveals that a predominant process affecting the transport of Benzene in a sandy soil is an irreversible sorption and/or degradation rather than retardation. Decay of Benzene through sorption and degradation increased with the addition of hydrogen peroxide and/or microorganism. Dissolved oxygen decreased with the increase of Benzene in all cases indicating that Benzene was degraded by dissolved oxygen. For BTCs with the addition of microorganisms (case 3 and case 4), microorganism showed much lower concentrations compared to the initial levels and an increasing tendency with time although concentrations of Benzene returned to zero, indicating a possible retardation of microorganism due to reversible and irreversible sorption to the particle surfaces.

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Studies on the Application of Microorganism to Control the Bulking of Paper Mill Wastewater (제지폐수 벌킹제어를 위한 미생물 적용 연구)

  • 이성호;조준형
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.34 no.3
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    • pp.32-37
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    • 2002
  • The paper mill wastewater actually generating bulking was used to apply to the spot. Batch and continuous type pilots were used in this study. Optimal time after propagating generation of activated sludge in aeration basin by adding Hoc forming microorganism was 24 and 36hours while optimal time of activated sludge in original aeration basin was 60hours. Showing the difference of sedimentation velocity at 7th day after operating a pilot continuously, SV30 was decreased to 50% at 13th day. COD value in aeration basin with floe forming microorganism was 35mg/L while COD value in original aeration basin was 52mg/L. It was indicated that application of Hoc forming microorganism can control the bulking of paper mill wastewater by shortening of recovery time and improving of pollution removal efficiency.

Comparative Study on Disinfection Efficiency of Chlorine and Chloramine in the Distribution Systems (배·급수계통에서 유리염소와 클로라민의 소독효과에 관한 비교연구)

  • Choi, Yong-Il;Nam, Sang-Ho
    • Journal of Korean Society of Water and Wastewater
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    • v.13 no.2
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    • pp.82-88
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    • 1999
  • This study was to evaluate disinfection efficiency of chlorine and chloramine as secondary disinfectants in the distribution systems. Indicator organism, HPC in the suspended and attached were measured for copper, galvanized steel, PVC, and carbon steel pipes. For suspended microorganism, the PVC pipe was markedly dense among the assessed pipe materials. The attached microorganism was markedly equivalent roughness of pipe materials. In copper and galvanized pipes, chloramine was more effective that free chlorine to disinfect suspended microorganism in the contact time of 2 hours. The contact time for the 99% inactivation of suspended microorganism by chloramine was longer than that of free chlorine. Regardless of pipe materials, chloramine was effective on both disinfection efficiency and 99% inactivation time for attached microorganism. In conclusion, chloramine which is good disinfectant for long contact time was recommended as secondary disinfectant in distribution system.

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The Study On the Distribution of Indoor Concentration of Microorganism in Commercial Building (다중이용시설의 실내공기 미생물 오염실태에 관한 연구)

  • Park Kyung-Su;Choi Sang-Gon;Hong Jin-Kwan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.18 no.8
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    • pp.620-626
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    • 2006
  • Recently, indoor air quality (IAQ) is one of the greatest problems in our modern societies. Although research for IAQ is made rapid progress but IAQ problems concerning in door microorganism contamination is required to be studied still more. So we have investigated the indoor microorganism concentration of a variety of department store, subway station, underground shopping center, kindergartens, library where people complain about the in-door air quality. The experiment on microorganism concentration of indoor air was carried out and the average of total microorganisms was measured. Comparing the experimental results with existing foreign criterion, the experimental results show that the ministry of environment recommendation microorganism concentration value ($800 CFU/m^3$) is in need of revision in the near future.

The Increase of Seeds Germination in Albizzia julibrissin, Lespedeza cyrtobotrya and Lespedeza cuneata by Microbial Treatment (미생물에 의한 자귀나무·참싸리·비수리 종자의 발아촉진)

  • Cha, Go-Woon;Hur, Young-Jin;Ahn, Tae-Young
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.11 no.3
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    • pp.107-115
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    • 2008
  • Herbs and plants widely used for the ecological restoration were selected for germination rate analysis under treatment of microorganisms to determine ideal treatment conditions and medium for enhanced germination rate. Albizzia julibrissin, when submerged in a nutrient medium or distilled water, presented a decrease in germination period rather than increase in germination rate. When treated with microorganism culture solution (JM-2) for 24 hours, 90% germination was achieved in two days, which is sufficient evidence to conclude that such treatment accelerates the germination of Albizzia julibrissin. Germination period decreased for Lespedeza cyrtobotrya samples submerged in microorganism solution for 15 and 48 hours, however, increases in germination rates were not observed. Sample treated in the solution for 24 hours had increased germination rate and enhanced germination period. Microorganism solution treatment had a negative effect on germination for Lespedeza cuneata, unlike Lespedeza cyrtobotrya and Albizzia julibrissin. Microorganism treated seeds of Lepsedeza cuneata had a lower germination rate than that of the control with no treatment. However, submerging treatments in a nutrient medium or distilled water for 24 to 48 hours were proven effective with higher germination rates than control sample with no treatment. Herbs and plants widely used for the ecological restoration were selected for germination rate analysis under treatment of microorganisms to determine ideal treatment conditions and medium for enhanced germination rate. Albizzia julibrissin, when submerged in a nutrient medium or distilled water, presented a decrease in germination period rather than increase in germination rate. When treated with microorganism culture solution (JM-2) for 24 hours, 90% germination was achieved in two days, which is sufficient evidence to conclude that such treatment accelerates the germination of Albizzia julibrissin. Germination period decreased for Lespedeza cyrtobotrya samples submerged in microorganism solution for 15 and 48 hours, however, increases in germination rates were not observed. Sample treated in the solution for 24 hours had increased germination rate and enhanced germination period. Microorganism solution treatment had a negative effect on germination for Lespedeza cuneata, unlike Lespedeza cyrtobotrya and Albizzia julibrissin. Microorganism treated seeds of Lepsedeza cuneata had a lower germination rate than that of the control with no treatment. However, submerging treatments in a nutrient medium or distilled water for 24 to 48 hours were proven effective with higher germination rates than control sample with no treatment.

Shortening of Fermentation Period of Changran-Jeotgal Using Microorganism (미생물을 이용한 창란젓갈의 숙성기간 단축)

  • YOON Ji-Hye;KANG Ji-Hee;PARK Mi-Ju;KIM Young-Ju;LEE Myung-Suk
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.36 no.4
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    • pp.327-332
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    • 2003
  • We Isolated strains of Micrococcus sp., Pseudomonas sp., Leuconostoc sp. which have protease activity in the Changran-Jeotgal. These microbes were added in the Changran-Jeotgal for the starters during fermentation to short fermentation period to check PH, VBN, $NH_2-N,$ free amino acids, and sensory evaluation. Microbiological changes were also examined for microorganism-added Changran-Jeotgal and the control. Viable cell counts in the microorganism-added Changran-Jeotgal increased from $7.1\times10^5\;CFU/g\;to\;7.5\times10^8\;CFU/g$ on 15th day, The cell counts in the control increased from $4.1\times10^5\;CFU/g\;to\;8.1\times10^8\;CFU/g$ on 30th day. VBN also increased in both. Increasing rates of $NH_2-N$ and free amino acids in the microorganism-added Changran-Jeotgal were faster than those in the control. Sensory evaluation showed that the microorganism-added Changran-Jeotgal was most favorable on 20th day. These results showed that fermentation period was shortened about 10 days in comparison with the control.

The control system of sludge amount inspection and discharge materials of outlet water and affiliated water-purification tank (오수/합병정화조의 배출물 제어시스템 연구)

  • 박주식;김건호;오지영;임총규;강경식
    • Proceedings of the Safety Management and Science Conference
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    • pp.193-202
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    • 2001
  • The individual rotten water purification tank recently discharges wastewater and sewage through the outlet without purification ability. The outlet water and affiliated water purification tank with microorganism cultivator tank cultivates microorganism and then drops the value BOD, COD of sewage and discharges the quality of water into the outlet. The blower and water pump operating continuously prompts the waste of energy and deterioration of equipment. Each room of deposition tank, foaming tank, microorganism cultivator tank is equipment with the sludge detection senses so it can detect the density of each room. The power-drive plant of the blower and water pump which ate the system cultivating the microorganism must be made as fuzzy controlization (If the sludge amount of each room become higher, the rate of operation of blower and water pump must heighten, on the contrary, in case of row sludge amount, the total handling amount and microorganism handling amount of each room of control. Tank reducing the rate of operation must be DB. At present, the blower amount in proportion to the sludge and oxygen demanding amount has to control. Each mom must be checked outlet level of the outlet, also each room must flow backward discharge materials, and must operate feed-back control until we want to be come as a below value of BOD/COD(10PPM ; KS).

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