• The Plant Pathology Journal
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• 제25권4호
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• pp.400-407
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• 2009

A pathogenesis-related protein (PgPR5) gene that isolated from the leaf of Panax ginseng was characterized. The ORF is 756 bp with a deduced amino acid sequence of 251 residues. The calculated molecular mass of the matured protein is approximately 27.5 kDa with a predicated isoelectric point of 7.80. A GenBank BlastX search revealed that the deduced amino acid of PgPR5 shares highest sequence similarity to PR5 of Actinidia deliciosa (80% identity, 87% similarity). PgPR5 has a C-terminal and N-terminal signal peptide, suggesting that it is a vacuolar secreted protein. The expression of PgPR5 under various environmental stresses was analyzed at different time points using real-time PCR. Our results reveal that PgPR5 is induced by salt stress, chilling stress, heavy metal, UV, and pathogen infection. These results suggest that the PgPR5 could play a role in the molecular defence response of ginseng to abiotic and pathogen attack. This is the first report of the isolation of PR5 gene from the P. ginseng.

• 한국콘텐츠학회논문지
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• 제16권5호
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• pp.660-667
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• 2016

원자력발전 등에 기인한 방사성 오염물질들은 대부분 제염과정을 통하여 방사능과 그 부피를 줄이는데, 물을 주로 사용하는 기존의 방사성 물질 제염방법은 많은 양의 2차 폐기물을 발생시킨다. 본 연구에서는 용매로 이산화탄소의 특성을 이용하여 폐기물 저감에 효과적인 제염 방법을 적용해보았다. 이를 위해 본 연구에서는 우선 원자력 오염물질의 제염 대상을 금속 이온, 금속과 금속산화물로 분류하여 두 가지 방법을 적용하였다. 전자의 경우 계면활성제 킬레이트법을 이용하여 제염하였다. 제염대상 핵종으로는 Sr, Co, Nb, Zr을 선정하였다. Sr과 Co는 각각 핵분열 생성물과 방사화 부식 생성물의 대표 핵종이고 Nb과 Zr은 오염된 방호복에서 가장 많은 방사능을 차지하는 핵종이다. Static Extraction을 통하여 Sr은 최고 97%, Nb과 Co, Zr은 각각 79%, 73%, 64%의 추출율을 얻었다.

• 열처리공학회지
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• 제19권4호
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• pp.200-207
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• 2006

In addition to the basic properties of the base and top coating agents, corrosion resistance of non-chrome magni 565 coating and characteristics of coating film when coated to steel substrate were studied. The system had a good wettability at room temperature. Moreover, both the contact angle and surface tension were affected little by the viscosity of coating agent and surface roughness of the steel substrate. And the samples coated with optimal conditions showed a great corrosion resistance in salt spray test with 1500 hours or longer of initial appearance time of rust. The coating film was composed of overlapping layer of zinc and aluminium flakes, and the thickness of base coat increased with an increase of base coat viscosity. Based on the C-F peaks of 1,1-Difluoroethaen homo-polymer, it was thought that the base coat was an inorganic polymer bond layer. Meanwhile, the top coat showed C-F peaks of polytetrafluoroethylene with C-H peaks of phenol in FT-IR analysis. From the lower weight loss of base coat in TG analysis, it was thought that cross linking density of base coat was larger than that of top coat. It was thought that the small exothermic reactions observed in DSC curves were due to the thermosetting resins contained in the coating agents. Compared to the non-coated specimen, the coated sample showed more higher polarization resistance and corrosion potential with lower corrosion current density.

• 한국재료학회지
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• 제22권5호
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• pp.227-236
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• 2012

Ionomer is a thermoplastic that is composed of covalent bonds and ionic bonds. It is possible to use this material in processes such as injection molding or extrusion molding due to the material's high oil resistance, weatherproof characteristics, and shock resistance. In this study, a new ionomer having a multifunctional group was prepared by a stepwise neutralization system with the addition of acidic and salt additives. In step I, to increase the contents of the multifunctional group and the acid degree in ethylene acrylic acid (EAA), MGA was added to the ionomer resin (EAA). A new ionomer was prepared via the traditional preparation method of the ionic cross-linking process. In step II, metal salt was added to the mixture of EAA and MGA. The extrusion process was performed using a twin extruder (L/D = 40, size : ${\varphi}30$). Ionomer film was prepared for evaluation of gas permeability by using the compression molding process. The degree of neutralized and ionic cross-linked new ionomer was confirmed by FT-IR and XRD analysis. In order to estimate the neutralization of the new ionomer film, various properties such as gas permeation and mechanical properties were measured. The physical strength and anti-scratch property of the new ionomer were improved with increase of the neutralization degree. The gas barrier property of the new ionomer was improved through the introduction of an ionic site. Also, the ionic degree of cross-linking and gas barrier property of the ionomer membrane prepared by stepwise neutralization were increased.

• 한국화재소방학회논문지
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• 제19권3호
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• pp.13-19
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• 2005

본 논문에서는 금속염 첨가제를 함유한 미분무수의 소화성능을 연구하고자 아세트산 나트륨을 함유한 단일 액적의 증발속도를 측정하였으며, small-scale 챔버내에서의 헵탄 pool fire에 대한 소화실험을 실시하여, 화염의 온도를 분석함으로써 첨가제에 의한 미분무수 소화특성을 분석하였다. 순수물과 수용액의 증발특성을 비교한 결과 핵비등 영역에서 온도가 높을수록 용해된 첨가제의 석출 및 표면장력의 변화 등 물리적 영향으로 순수물에 비해 수용액의 증발속도가 현저히 느리게 나타났다. 소화실험 결과, 저압에서는 물 액적이 화염의 플림을 뚫지 못하기 때문에 소화는 이루어지지 않았고 단순히 화염의 크기를 작아지게 하였다. 중압에서는 첨가제를 넣었을 경우 액적의 운동량 증가에 따른 물리적 소화효과와 첨가제의 화학적 소화효과가 상승작용을 하여 화염을 억제하였고, 고압에서는 미분무수 시스템의 주요 소화 메커니즘 이외에도 blowing효과에 의해서 화염이 소화되는 것을 관찰할 수 있었다.

• Nuclear Engineering and Technology
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• 제9권2호
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• pp.75-81
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• 1977

원자력 발전소에서 나오는 방사성 핵종이 clay 속에 고정되는 반응기구를 분석하기 위해서 clay의 양이온 교환능을 Sawhney 방법으로 측정했다. Clinoptilolite, vermiculite 및 sodalite들의 PH dependent CEC를 측정한 결과 총 양이온 교환능의 약 70% 정도가 영구 고정되어진다고 생각되는 neutral salt CEC에 의해 일어나고 나머지는 가역과정인 clay 속의 유기물질과 다른 급속(Al, Mg)의 치환에 의해서 일어난다는 결론을 얻었으며, pH 9 이상에서 clay에 의한 방사성 핵종의 제거는 이온 교환 기구에 의한 고정보다 오히려 중금속 이온의 침전에 의해서 더 많이 일어난다는 것도 밝혀냈다. 그리고 연속 치환에 의해서 처리된 Na-clay는 방사성 핵종제거에 상당히 향상된 제거 효율을 나타내고 있다.

• 한국염색가공학회지
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• 제6권1호
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• pp.33-43
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• 1994

In the present work, to clarify the mechanism of the neutral salt effect on the alkaline hydrolysis of PET, many salts with different cations like LiCl, NaCl, KCl, CsCl were added to the aqueous alkaline solutions. Then PET was hydrolyzed with aqueous solutions of many salts in alkali metal hydroxides under various conditions. Some conclusions obtained from the experimental results were summarized as follows. The reaction rate of the alkaline hydrolysis of PET was increased by the addition of neutral salts and In k was increased nearly linearly with the square root of ionic strength of reaction medium. This fact suggested that the ionic strength effect by Debye-Huckel and Bronsted theory was exerted on the reaction. The specific salt effect was also observed. The reaction rate was increased with the increase in the electrophilicity of cations of neutral salts, i. e., in the order of $Cs^+$/ < $K^+$/ $a^+$/ $i^$^+$. It was considered that the reaction rate was increased in the order of C $s^+$. < $K^+$. $a^+$. $i^+$. because the lowering effect of the cations on the negative charge of PET surface was increased with the electrophilicity of cations. It was thought that $E_{a}$ was increased because the cations of neutral salts decreased the negative charge of PET surface. It, however, was inferred from the increase in ${\Delta}$S＊ and the decrease in the ${\Delta}$G＊ that the cations of neutral salts associated with PET increased the collision frequency between carbonyl carbon and OH- ion and then accelerated the reaction rate.te.

• Journal of Microbiology and Biotechnology
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• 제26권8호
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• pp.1375-1382
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• 2016

The extremely halophilic archaeon Halobacterium noricense is a member of the genus Halobacterium. Strain CBA1132 (= KCCM 43183, JCM 31150) was isolated from solar salt. The genome of strain CBA1132 assembled with 4 contigs, including three rRNA genes, 44 tRNA genes, and 3,208 open reading frames. Strain CBA1132 had nine putative CRISPRs and the genome contained genes encoding metal resistance determinants: copper-translocating P-type ATPase (CtpA), arsenical pump-driving ATPase (ArsA), arsenate reductase (ArsC), and arsenical resistance operon repressor (ArsR). Strain CBA1132 was related to Halobacterium noricense, with 99.2% 16S rRNA gene sequence similarity. Based on the comparative genomic analysis, strain CBA1132 has distinctly evolved; moreover, essential genes related to nitrogen metabolism were only detected in the genome of strain CBA1132 among the reported genomes in the genus Halobacterium. This genome sequence of Halobacterium noricense CBA1132 may be of use in future molecular biological studies.

• Nuclear Engineering and Technology
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• 제53권12호
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• pp.3879-3891
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• 2021

A heat pipe residual heat removal system is proposed to be incorporated into the reactor driven subcritical (RDS) facility, which has been proposed by MIT Nuclear Reactor Laboratory for testing and demonstrating the Fluoride-salt-cooled High-temperature Reactor (FHR). It aims to reduce the risk of the system operation after the shutdown of the facility. One of the main components of the system is an air-cooled heat pipe heat exchanger. The alkali-metal high-temperature heat pipe was designed to meet the operation temperature and residual heat removal requirement of the facility. The heat pipe model developed in the previous work was adopted to simulate the designed heat pipe and assess the heat transport capability. 3D numerical simulation of the subcritical facility active zone was performed by the commercial CFD software STAR CCM + to investigate the operation characteristics of this proposed system. The thermal resistance network of the heat pipe was built and incorporated into the CFD model. The nominal condition, partial loss of air flow accident and partial heat pipe failure accident were simulated and analyzed. The results show that the residual heat removal system can provide sufficient cooling of the subcritical facility with a remarkable safety margin. The heat pipe can work under the recommended operation temperature range and the heat flux is below all thermal limits. The facility peak temperature is also lower than the safety limits.

• 한국건설순환자원학회논문집
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• 제1권2호
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• pp.136-143
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• 2013

하수시설 및 복개 구조물 등은 용해 시 산성으로 작용하는 황화수소에 크게 노출되어, 황산화균의 작용에 의해 강산성의 황산이온이 생성된다. 이에 따라 콘크리트의 생화학적 부식에 의한 열화가 촉진되며, 콘크리트 손상을 더욱 가속화하여 내구성이 크게 저하될 수 있다. 본 연구에서는 콘크리트에서 황산화균이 유기 생체적으로 사용하는 황화수소를 제거하기 위해, 금속의 살균성을 이용하여 금속 및 금속염 분말을 콘크리트에 혼입한 후, 황산화 억제 성능을 평가하였다. 이를 위해 중성화한 콘크리트 시편의 황산화균에 대한 항균 성능을 비교 평가하였고, 급속 염소이온 침투시험을 통해 금속 및 금속염계 항균제 첨가량에 따른 콘크리트 염화물 침투깊이 및 확산계수를 측정하였다. 또한 야외에서 폭로시킨 콘크리트 시편의 표면 상태의 생화학적 상태를 관측하여, 항균콘크리트의 성능 및 적용성을 확인하였다.