• 상하수도학회지
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• 제20권1호
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• pp.44-52
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• 2006

Bio-filtration processes using honeycomb tubes (process 1) and aeration and manganese-sand filtration (process 2) were evaluated for the biological manganese removal efficiency. The concentration of manganese at effluent was stabilized after 20days operation in process 1. It was estimated the required time for attaching and growing microorganisms to honeycomb tubes. In long term of operation periods, manganese removal efficiency was dropped for the excessively attached biofilm and manganese dioxide to honeycomb tubes. It took several days for normal operation in process 2, after that manganese removal efficiency was increased to 98% and stabilized for 1.5 years. Microorganisms in process 1 and 2 were isolated and cultured to characterize manganese-oxidizing bacteria. Among the four types of colony, light brown colony was turned blue color by leuco crystal violet spot test. Stenotropomonas genus, known as manganese-oxidizing bacteria, was identified by 16S rDNA partial sequencing analysis which was isolated in process 1 and 2. For the biological treatment to remove manganese, these two considerations are important. One is to choose the proper media attaching manganese oxidant, another one is to define the cultural condition of isolated manganese-oxidizing bacteria.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.275-280
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• 2001

Typically, manganese (II) ions are incompletely removed from water as $MnO_2$ on increasing the pH of the water to 10. The water then has to be neutralized before it can be used. We propose a new and effective method for removing Mn (II) from water using a new combination of symbiotic microbes consisting of manganese-oxidizing bacteria and filamentous algae. The microbes rapidly oxidize Mn(II) to Mn (IV) at a neutral pH with no organic matter required as a nutrient and $MnO_2$is precipitated immediately. This differs from the use of heterotrophic manganese-oxidizing bacteria where organic nutrients are required. Our results suggest that this method will be useful in developing new systems for removal of manganese(II) ions from industrial and mining wastewater and drinking water. In addition, there are other possibilities such as recycling of dry batteries which are presently discarded without treatment

• 대한환경공학회지
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• 제35권8호
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• pp.564-570
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• 2013

산성광산배수처리를 위한 국내 대부분의 처리시설은 자연정화법을 사용하고 있으며 이들 중 일부 처리장에서는 고농도의 망간이 유출되고 있는데 이는 망간산화를 위해 높은 pH (>9)가 요구되기 때문이다. 본 연구는 망간처리 공정 중 경제성을 높일 수 있는 생물학적 망간처리의 가능성을 타진하는데 그 목적이 있으며 망간산화미생물은 Pseudomonas sp. MN5를 이용하였다. 회분식 실험을 통해 수질조건에 따른 영향을 분석한 결과 pH 7에서 최고산화속도는 $10.4mg/L{\cdot}h$로 나타났다. 망간산화미생물을 담지한 연속류 실험결과 운전 초기 망간 농도는 42 mg/L에서 6 mg/L 이하로 크게 감소하였지만 망간산화미생물의 산소소비에 의한 혐기조건 형성으로 망간의 재용출 현상이 나타났다.

• 상하수도학회지
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• 제24권3호
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• pp.341-349
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• 2010

It is well known that manganese is hard to oxidize under neutral pH condition in the atmosphere while iron can be easily oxidized to insoluble iron oxide. The purpose of this study is to identify removal mechanism of manganese in the D water treatment plant where is treating bank filtered water in aeration and rapid sand filtration. Average concentration of iron and manganese in bank filtered water were 5.9 mg/L and 3.6 mg/L in 2008, respectively. However, their concentration in rapid sand filtrate were only 0.11 mg/L and 0.03 mg/L, respectively. Most of the sand was coated with black colored manganese oxide except surface layer. According to EDX analysis of sand which was collected in different depth of sand filter, the content of i ron in the upper part sand was relatively higher than that in the lower part. while manganese content increased with a depth. The presence of iron and manganese oxidizing bacteria have been identified in sand of rapid sand filtration. It is supposed that these bacteria contributed some to remove iron and manganese in rapid sand filter. In conclusion, manganese has been simultaneously removed by physicochemical reaction and biological reaction. However, it is considered that the former reaction is dominant than the latter. That is, Mn(II) ion is rapidly adsorbed on ${\gamma}$-FeOOH which is intermediate iron oxidant and then adsorbed Mn(II) ion is oxidized to insoluble manganese oxide. In addition, manganese oxidation is accelerated by autocatalytic reaction of manganese oxide. The iron and manganese oxides deposited on the surface of the sand and then are aged with coating sand surface.

• 한국광물학회지
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• 제23권2호
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• pp.161-170
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• 2010

많은 미생물들이 수용성 망간이온($Mn^{2+}$)을 불용성인 산화망간($Mn^{4+}$) 광물로 산화 침전시키는데, 이와 같은 생물학적 산화반응은 비생물학적 산화반응보다 훨씬 빠르게 일어난다. 이처럼 미생물에 의해 생성된 바이오 산화망간 광물은 표면의 강한 흡착성과 산화환원 반응을 통해 생지구화학 순환과 환경오염물질의 생물흡수도에 큰 역할을 한다. 본 논평은 양자역학의 밀도범함수 이론에 바탕을 둔 전산모사를 이용하여 산화망간 광물 표면의 독성금속 흡착의 자세한 기작과 망간원자 빈자리의 광화학적 역할을 새롭게 밝힌 최근 연구결과를 소개한다.

• Molecules and Cells
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• 제23권3호
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• pp.370-378
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• 2007

A superoxide dismutase was purified 62-fold in seven steps to homogeneity from Methylobacillus sp. strain SK1, an obligate methanol-oxidizing bacterium, with a yield of 9.6%. The final specific activity was 4,831 units per milligram protein as determined by an assay based on a 50% decrease in the rate of cytochrome c reduction. The molecular weight of the native enzyme was estimated to be 44,000. Sodium dodecyl sulfate gel electrophoresis revealed two identical subunits of molecular weight 23,100. The isoelectric point of the purified enzyme was found to be 4.4. Maximum activity of the enzyme was measured at pH 8. The enzyme was stable at pH range from 6 to 8 and at high temperature. The enzyme showed an absorption peak at 280 nm with a shoulder at 292 nm. Hydrogen peroxide and sodium azide, but not sodium cyanide, was found to inhibit the purified enzyme. The enzyme activity in cell-free extracts prepared from cells grown in manganese-rich medium, however, was not inhibited by hydrogen peroxide but inhibited by sodium azide. The activity in cell extracts from cells grown in iron-rich medium was found to be highly sensitive to hydrogen peroxide and sodium azide. One mol of native enzyme was found to contain 1.1 g-atom of iron and 0.7 g-atom of manganese. The N-terminal amino acid sequence of the purified enzyme was Ala-Tyr-Thr-Leu-Pro-Pro-Leu-Asn-Tyr-Ala-Tyr. The superoxide dismutase of Methylobacillus sp. strain SK1 was found to have antigenic sites identical to those of Methylobacillus glycogenes enzyme. The enzyme, however, shared no antigenic sites with Mycobacterium sp. strain JC1, Methylovorus sp. strain SS1, Methylobacterium sp. strain SY1, and Methylosinus trichosproium enzymes.

• 한국토양비료학회지
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• 제17권3호
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• pp.289-298
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• 1984

논토양(土壤)에 볏짚을 시용(施用)하고 투수(透水) 조건하(條件下)에서 수도(水稻)를 재배(栽培)하면서 유기물분해(有機物分解)에 관여(關與)하는 미생물(微生物)의 소장(消長)과 볏짚분해율(分解率)을 조사(調査), 검토(檢討)한 결과(結果)는 다음과 같다. 전세균수(全細菌數)는 초기(初期)에 증가(增加)되었으며 일반적(一般的)으로 토층(土層)이 하층(下層)보다 많았고 사상균수(絲狀菌數)는 경시적(經時的)으로 감소(減少)하는 경향(傾向)을 보였다. Cellulose분해균중(分解菌中) 호기성균(好氣性菌)은 경시적(經時的)으로 감소(減少)하여 하층(下層)의 균수(菌數)가 상층(上層)보다 많았다. Glucose이용균(利用菌)과 황산환원균(黃酸環元菌)은 볏짚 시용(施用)으로 균수(菌數)가 증가(增加)하고 투수(透水)에 의(依)하여 감소(減少)되었다. 망간산화균(酸化菌)은 볏짚시용(施用)의 영향(影響)은 뚜렷하지는 않았으나 경시적(經時的)으로 증가(增加)하는 경향(傾向)이었다. 투수중(透水中)에 용탈(溶脫)된 미생물(微生物)은 토양중(土壤中) 하층토(下層土)의 미생물(微生物)의 소장(消長)과 동일(同一)하나 다만 그 수(數)가 1/10정도(程度)로 낮았다. 논토양(土壤)에 매설(埋設)된 볏짚은 수도재배기간중(水稻栽培其間中) 약40%가 분해(分解)되었다. 시용(施用)볏짚중(中) Cellulose는 재배기간(栽培其間)에 약 30%가 분해(分解)되었으며 lignin은 약(約)60%가 분해(分解)되었다. 볏짚중 질소(窒素)는 약(約)70~80%가 잔존(殘存)하고 있다.