• BMB Reports
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• 제39권4호
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• pp.464-467
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• 2006

Recently, the nucleotide sequences of entire genomes became available. This information combined with older sequencing data discloses the exact chromosomal location of millions of nucleotide markers stored in the databases at NCBI, EMBO or DDBJ. Despite having resolved the intron/exon structures of all described genes within these genomes with a stroke of a pen, the sequencing data opens up other interesting possibilities. For example, the genomic mapping of the end sequences of the human, murine and rat BAC libraries generated at The Institute for Genomic Research (TIGR), reveals now the entire encompassed sequence of the inserts for more than a million of these clones. Since these clones are individually stored, they are now an invaluable source for experiments which depend on genomic DNA. Isolation of smaller fragments from such clones with standard methods is a time consuming process. We describe here a reliable one-step cloning technique to obtain a DNA fragment with a defined size and sequence from larger genomic clones in less than 48 hours using a standard vector with a multiple cloning site, and common restriction enzymes and equipment. The only prerequisites are the sequences of ends of the insert and of the underlying genome.

• 화약ㆍ발파
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• 제34권4호
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• pp.28-34
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• 2016

화약류, 인화성 액체와 가스 또는 먼지 등의 폭발에 의해 유발된 폭발효과를 평가하는데 경험적모델, 현상학적모델 및 전산유체역학모델이 사용된다. 경험적모델의 한 종류인 TNT등가법은 사용이 매우 단순하기 때문에 현재까지도 널리 사용되고 있다. 본 연구에서는 TNT 폭발 실험으로부터 얻어진 최대과압-환산거리 곡선과 환산충격량-환산거리 곡선을 피팅하여 새로운 회귀식을 유도하였다. 폭발성 물질의 TNT 등가질량만 알면 본 연구에서 유도한 회귀식을 이용하여 거리에 따른 최대과압과 충격량을 평가하는 것이 가능하다. TNT등가법의 한 성분인 수율계수의 크기를 달리하여 최대과압을 구한 결과 압력의 증가가 급격히 나타나는 폭원으로부터 근접한 거리에서는 수율계수에 따라 최대과압의 차가 크게 발생하는 반면에 거리가 증가함에 따라 그 차이는 감소하는 것으로 나타났다.

• Journal of Electrical Engineering and Technology
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• 제10권5호
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• pp.2046-2051
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• 2015

Currently, most high-voltage gas circuit breakers (CBs) include asymmetrical geometries in the shield, the tank, the hot-gas exhaust, and the connection parts for bushings. For this reason, a 3-dimensional (3-D) analysis of the insulation capability is necessary, rather than a 2-D analysis. However, a 3-D analysis has difficulties due to the computational time and complex modeling. This paper presents a 3-D analysis considering the asymmetry in high-voltage gas CBs and a technique to reduce the calculation time. In the proposed technique, the arc plasma requiring the most computational time is first calculated by a 2-D analysis. Then, the results such as pressure, temperature, and velocity are input as a source for the 3-D analysis. This technique is applied to a 145kV self-blast-type CB and the analysis result exhibits good agreement with the experimental result.

• Journal of Microbiology and Biotechnology
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• 제16권7호
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• pp.1158-1162
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• 2006

The glyoxylate cycle can conserve carbons and adequately supply tricarboxylic acid (TCA) cycle intermediates for biosynthesis when microorganisms grow on $C_{2}$ carbon sources. It has been reported that isocitrate lyase (ICL1), a key enzyme of the glyoxylate cycle, is highly induced when Magnaporthe grisea, the causal agent of rice blast, infects its host. Therefore, the glyoxylate cycle is considered as a new target for antifungal agents. A 1.6-kb DNA fragment encoding the ICL1 from M. grisea KJ201 was amplified by PCR, cloned into a vector providing His-tag at the N-terminus, expressed in Escherichia coli, and purified using Ni-NTA affinity chromatography. The molecular mass of the purified ICL1 was approximately 60 kDa, as determined by SDS-PAGE. The ICL1 inhibitory effects of TCA cycle intermediates and their analogs were investigated. Among them, 3-nitropropionate was found to be the strongest inhibitor with an $IC_{50}$ value of $11.0{\mu}g/ml$. 3-Nitropropionate inhibited the appressorium development in M. grisea at the ${\mu}M$ level, whereas conidia germination remained unaffected. This compound also inhibited the mycelial growth of the fungus on minimal medium containing acetate as a $C_{2}$ carbon source. These results suggest that ICL1 plays a crucial role in appressorium formation of M. grisea and is a new target for the control of phytopathogenic fungal infection.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2012년도 추계총회 및 학술대회 논문집
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• pp.185-185
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• 2012

최근 자연모사를 이용한 연구가 다양한 분야에 적용되고 있다. 특히 연 잎의 표면에서 나타나는 초발수 특성이 마이크로 나노 크기의 구조와 표면에너지를 제어하는 에피큐티클 왁스에 기인하다는 것이 밝혀지면서 이를 응용한 연구가 진행되고 있다. 본 연구는 알루미늄 표면처리로 마이크로와 나노 구조물을 형성하고 그 위에 발수 특성을 가진 물질을 증착하여, 발수성을 가지는 표면을 개발하였다. 알루미늄 표면에 마이크로 크기의 알루미나($Al_2O_3$) 분말을 이용한 블라스트(blast) 공정으로 표면에 마이크로 구조를 형성하고, Linear Ion Source(LIS)를 적용한 Ar 이온빔 에칭으로 나노 구조를 형성하였다. FE-SEM 분석을 통해 수~수십 마이크로 구조 위에 나노 크기의 구조가 형성 된 것을 관찰하였다. 마이크로 나노 구조가 형성된 알루미늄의 표면에너지를 낮추기 위해 trimethylsilane(TMS) 및 Ar을 이용한 플라즈마처리로 표면에 기능성 코팅막을 형성하였다. 그 결과 TMS 발수 코팅하기 전에 비해 표면에너지가 $99.75mJ/m^2$에서 $9.05mJ/m^2$으로 급격히 낮아지고 접촉각 값이 $123^{\circ}$로 향상된 것을 확인하였다.

• 자원리싸이클링
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• 제5권4호
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• pp.17-24
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• 1996

The computer simulation model was established to verify the applicability of smelting reduction concept to treatment of industrial wastes which becomes issue on the enviromental and recycling view point. Computer simulation model provides as following results. The increase of post combustion ratio(PCR) and heat transfer efficiency of PC energy(HTE) is effective ways to save energy. But, in order to increase PCR, recovery efficiency of post combustion energy(HTE) have to be higher than 85% HTE considering refractory life and saving energy together. Coke is most useful fuel source because it shows lowest dependence of PCR and low hydrogen content. The quality of hot metal of current process would be expected to the similar level with that of blast furnace. The utilization of scrap and Al dross can be also possible to maximize the advantages of current process which is high temperature and chemical dilution with hot metal and slag. In case of scrap, energy consumption was slightly increases because of heating up energy of scrap. Consquently, current process concept provides the possibility of intergrating recycles of industrial wastes materials such as EAF slag, coke oven dust, life terminated acidic refractory, aluminium dross and scrap by smelting reduction process.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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• pp.320-324
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• 2004

Laser Propulsion is a device that generates thrust using laser energy. Laser-driven In-Tube Accelerator (LITA) has been developed at Tohoku University. LITA is a laser propulsion system that accelerates an object not in an open air but in a tube. Experiments of vertical launching and pressure measurement on the tube wall were carried out and in order to observe the initial state of plasma and blast wave, the visualization experiment was carried out using the shadowgraph method. In this study, the time variation of pressure on the tube wall is numerically simulated solving Euler equation. In order to model the laser energy, heat source function added to the frozen flow Euler equation. Plasma size from the shadowgraph images was used for the initial condition of laser energy input. For verification of the modeling, these results were compared with the previous experimental and numerical results. From these verifications, an analysis of LITA performance will be investigated.

• 한국수소및신에너지학회논문집
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• 제30권2호
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• pp.111-118
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• 2019

Greenhouse gas emissions have a profound effect on global warming. Various environmental regulations have been introduced to reduce the emissions. The largest amount of greenhouse gases, including carbon dioxide, is produced in the steel industry. To decrease carbon dioxide emission, hydrogen-based iron oxide reduction, which can replace carbon-based reduction has received a great attention. Iron production generates various by-product gases, such as cokes oven gas (COG), blast furnace gas (BFG), and Linz-Donawitz gas (LDG). In particular, COG, due to its high concentrations of hydrogen and methane, can be reformed to become a major source of hydrogen for reducing iron oxide. Nevertheless, continuous COG cannot be supplied under actual operation condition of steel industry. To solve this problem, this study proposed to use two alternative COG-based fuel mixtures; one with natural gas and the other with biogas. Reforming study on two types of mixed gas were carried out to evaluate catalyst performance under a variety of operating conditions. In addition, methane conversion and product composition were investigated both theoretically and experimentally.

• The Plant Pathology Journal
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• 제37권4호
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• pp.389-395
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• 2021

Soil is the major source of plant-associated microbes. Several fungal and bacterial species live within plant tissues. Actinomycetes are well known for producing a variety of antibiotics, and they contribute to improving plant health. In our previous report, Streptomyces globisporus SP6C4 colonized plant tissues and was able to move to other tissues from the initially colonized ones. This strain has excellent antifungal and antibacterial activities and provides a suppressive effect upon various plant diseases. Here, we report the genome-wide analysis of antibiotic producing genes in S. globisporus SP6C4. A total of 15 secondary metabolite biosynthetic gene clusters were predicted using antiSMASH. We used the CRISPR/Cas9 mutagenesis system, and each biosynthetic gene was predicted via protein basic local alignment search tool (BLAST) and rapid annotation using subsystems technology (RAST) server. Three gene clusters were shown to exhibit antifungal or antibacterial activity, viz. cluster 16 (lasso peptide), cluster 17 (thiopeptide-lantipeptide), and cluster 20 (lantipeptide). The results of the current study showed that SP6C4 has a variety of antimicrobial activities, and this strain is beneficial in agriculture.

• Advances in concrete construction
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• 제12권6호
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• pp.499-505
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• 2021

Geopolymer binders fascinate the attention of researchers as a replacement to cement binder in conventional concrete. One-ton production of cement releases one ton of carbon-dioxide in the atmosphere. In the replacement of cement by geopolymer material, there are two advantages: one is the reduction of CO₂ in the atmosphere, second is the utilization of Fly ash and Ground granulated blast furnace slag (GGBFS) are by-products from coal and steel industries. This paper focuses on the mechanical properties of steel fiber reinforced geopolymer concrete. The framework considered in this research work is geopolymer source (Fly ash, GGBFS and crimped steel fibre) and alkaline activator which consists of NaOH and Na₂SiO₃ of molarity 8M. Here the Na₂SiO₃ / NaOH ratio was taken as 2.5. The variables considered in this experimental work include Binder content (360,420 and 450 kg/m³), the proportion of Fly ash and GGBS (70-30, 60-40 and 50-50) for three different grades of Geopolymer concrete (GPC) GPC 20, GPC 40 and GPC 60. The percentage of crimped steel fibres was varied as 0.1%, 0.2%, 0.3%, 0.4% and 0.5%. Generally, the inclusion of steel fibres increases the flexural and split tensile strength of Geopolymer concrete. The optimum dosage of steel fibres was found to be 0.4% (by volume fraction).