• 한국연소학회:학술대회논문집
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• 대한연소학회 2003년도 제27회 KOSCO SYMPOSIUM 논문집
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• pp.209-214
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• 2003

Numerical simulations are performed at atmospheric pressure in order to understand the effect of additives on flame speed, flame temperature, the radical concentration, the NOx formation in freely propagating $CH_4/O_2/N_2$ flames. The additives used are carbon dioxide and hydrogen chloride which have a combination of physical and chemical behavior on hydrocarbon flame. In the flame established with the same mole of methane and additive, $CO_2$ addition significantly contributes toward the reduction of flame speed and flame temperature by the physical effect, whereas addition of HCl mainly does by the chemical effect. The impact of HCl addition on the decrease of the radical concentration is about 1.6-1.8 times as large as $CO_2$ addition. Hydrogen chloride addition is higher on the reduction of EINO than $CO_2$ addition because of the chemical effect of HCl.

• Journal of Microbiology and Biotechnology
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• 제14권1호
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• pp.48-55
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• 2004

Six strains of an obligate predatory bdellovibrio isolate that preys on Burkholderia glumae in rice paddy field water and rhizosphere soil, were identified and characterized. The numbers of Bdellovibrio cells varied from $3.2{\times}10^3$ to $9.2{\times}10^3$ plaque-forming unit/g after enrichment in cells of B. glumae. Prey range tests with six Bdellovibrio strains and 17 prey strains of rice-pathogenic, antibiosis-related, or nitrogen-fixing bacteria resulted in unique predation patterns in related prey cells. Strain BG282 had the widest prey range on 7 plant pathogenic bacteria among the 17 prey strains tested. However, no predation occurred with strains of Azospirillum brasilense, Paenibacillus polymyxa, Pseudomonas fluorescens, P. putida, and Serratia marcescens that are associated with antibiosis or nitrogen fixation in the rice ecosystem. Identification was confirmed by the presence of typical bdelloplast in the prey cells of B. glumae and by a PCR assay using B. bacteriovorus-specific primers. Furthermore, 16S rDNA sequencing of the six bdellovibrio strains showed a homology range of 97.2% to 99.2% to the type strain of B. bacteriovorus.

• Journal of Microbiology and Biotechnology
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• 제22권4호
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• pp.457-461
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• 2012

Members of candidate division OP3 were detected in 16S rRNA gene clone libraries from methanogenic enrichment cultures that utilized limonene as a carbon and energy source. We developed probes for the visualization of OP3 cells. In situ hybridization experiments with newly designed OP3-specific probes [OP3-565 and Eub-338(VI)] revealed abundant small OP3 cocci attached to larger cells. Syntrophic Deltaproteobacteria, OP3 cells, and methanogens affiliating with Methanoculleus and Methanosaeta formed the limonene-degrading community.

• Journal of Microbiology and Biotechnology
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• 제20권11호
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• pp.1571-1576
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• 2010

Two bacterial strains designated as CT2 and CT5 were isolated from highly alkaline cement samples using the enrichment culture technique. On the basis of various physiological tests and 16S rRNA sequence analysis, the bacteria were identified as Bacillus species. The urease production was 575.87 U/ml and 670.71 U/ml for CT2 and CT5, respectively. Calcite constituted 27.6% and 31% of the total weight of sand samples plugged by CT2 and CT5, respectively. Scanning electron micrography analysis revealed the direct involvement of these isolates in calcite precipitation. This is the first report of the isolation and identification of Bacillus species from cement. Based on the ability of these bacteria to tolerate the extreme environment of cement, they have potential to be used in remediating the cracks and fissures in various building or concrete structures.

• 유기물자원화
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• 제4권2호
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• pp.71-75
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• 1996

Trimethylamine, dimethylamine, methylamine 등의 아민류를 분해할 수 있는 미생물을 TMA를 성장기질로 사용한 농화배양으로부터 분리하였다. 분리된 균은 Methylobacterium sp. T32에 속하는 균으로 동정되었다. 이 균은 메탄올, 메틸아민류를 분해할 수 있으나, 다탄소화합물중에서는 malate, succinate, betaine과 같이 극히 제한된 종류의 유기화합물만을 분해할 수 있는 restricted facultative methylotroph였다. 이 균을 분변토에 고정하여 biofilter를 제작하였을 때 TAM gas를 SV $30h^{-1}$, 농도 120ppm를 연속적으로 분해했다.

• 한국미생물·생명공학회지
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• 제17권3호
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• pp.252-256
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• 1989

해수환경에서 Bunker-C유를 가장 강력히 유화분산시키는 Acilromobacter sp. M-1220 균주를 대상으로 하여 생물유화제물질의 생성 및 그 성질을 조사하여 본 결과 유화제물질은 hexadecane oil 배지를 사용하여 18$^{\circ}C$에서 대수증식기 중기때에 가장 많이 생성되었다. 그리고 이는 양이온성의 peptidolipid 물질인 것으로 여겨지며 원유와 몇 종의 식용유에도 강한 유화안정능력을 보였다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2002년도 제25회 KOSCI SYMPOSIUM 논문집
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• pp.41-47
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• 2002

Oxygen has been used extensively in various industries for many years. Despite earlier successful attempts to use oxygen in industrial combustion furnaces, its full theoretical researches have only recently begun to be realized. The aim of this study is to investigate the effect of oxygen enriched combustion. This paper analyzes the characteristics of oxygen enriched combustion, and deals with the experimental investigation of the flame temperature and NOx concentration in exhaust gas. The flame temperature, concentration of exhaust gas were measured and flame configurations were photographed according to the variation of oxygen concentrations in oxidizer.

• 한국초등수학교육학회지
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• 제2권1호
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• pp.41-59
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• 1998

수학 영재 교육이 정상적으로 이루어지기 위해서는 제도적인 운영 체제와 적절한 교육 프로그램의 뒷받침이 이루어져야 한다. 우선, 수학 영재의 특성을 파악하기 위한 적절한 판별 도구의 개발이 필요하다. 영재를 지도하는 교사의 책임도 막중하며, 다양한 형태의 수업 방법과 학습 환경이 제공되어야 한다. 또한 새로운 자료의 개발과 활용에 보다 세심한 배려가 필요하다. 아울러 학생과 프로그램 평가에 대한 연구가 뒷받침되어야 할 것이다.

• 대한수의학회지
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• 제13권1호
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• pp.31-34
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• 1973

Investigations of the prevalence of SalmoneIla organisms in chicken of Suwon area and the effect of selenite broth on the growth of Sal. pullorum were made. The results obtained were summarized as foIlowings. 1. Salmonella organisms was not isolated from fecal samples of 357 chicken from 6 poultry farms of Suwon area. 2. In selenite broth, the growth of Sal. pullorum was completely inhibited may due to the toxic effect of the medium when the inoculum contained less than $5{\times}10^3$ organisms. However, enrichment was attained overcoming the inhibitory action of the medium when $5{\times}10^3$ or more organisms were inoculated.

• 한국산업융합학회 논문집
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• 제2권2호
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• pp.83-90
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• 1999

A cellulose acetate membrane containing silver nitrate was prepared by gelatinizing in water at $2^{\circ}C$ after evaporating solvent from the casting solution on a glass plate. Permeation experiments for oxygen and nitrogen were conducted in the ranges of temperature, $5-40^{\circ}C$ and pressure difference, $1-5kg/cm^2$ in order to investigate the effects of temperature and pressure difference on permeation characteristics of the membrane. When the evaporation time was increased, the permeability of oxygen decreased but the separation factor of oxygen against nitrogen increased since a more dense layer was formed on the membrane surface. When the silver nitrate was added, the permeation flux was doubled and the separation factor was improved from 3.0 to 3.3. This implies that silver nitrate acts as an oxygen carrier in the membrane.