• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.801-804
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• 2008

Performance for the resistant to chlorides penetration is required in order to increase durability of seaside construction. For this reason, it is important to acquire simultaneously watertightness, resistance for crack of concrete and chemical fixation effect of chloride in it. In this study, High durability promoting agents(HD) consist of inorganic salt and active components were applied to enhancing resistance for chloride ion penetration against concrete based on mix(composition of binder : OPC+SLG) of seaside construction. Tang's experimental method was utilized to investigate the resistances of chloride ion penetration of concrete such as chloride ion diffusion coefficient and penetration depth. It was confirmed that resistance of chloride ion penetration of concrete by 0.6% addition of HD was improved to $11.3^{\sim}20.5$% than non-added concrete.

• Proceedings of the Membrane Society of Korea Conference
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• 1993.04a
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• pp.30-30
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• 1993

막 자체가 갖는 성능은 역삼투공정의 효율성에 영향을 미치는 상당히 중요한 인자이다. 따라서 역삼투막이 가져야 할 조건은 높은 염배제율 뿐만아니라 물의 투과유량도 커야하며, 가수분해나 산화에 의한 성능저하가 없어야 한다. 폴리아미드막을 이용한 역삼투공정은 이미 보편화되어 있으며, 특히 가교폴리아미드를 선택층으로 가지는 박층복합막은 그 성능이 우수한 것으로 알려져왔다. 폴리아미드막은 우수한 물투과유량 및 염배제율을 가지고 있어 이미 상품화 되어있지만 내화학성의 향상에 있어서는 아직도 연구개발중에 있으며, 특히 막세척시 사용되는 염소에 대한 저항성 향상이 절실히 요구되고 있는 실정이다.

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.279-282
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• 2001

Oxi-PAN(Oxidized PAN, Oxi-PAN)섬유는 PAN 섬유를 1-2$^{\circ}C$/min정도의 승온 속도로 180-30$0^{\circ}C$ 정도의 저온, 산화 분위기에서 인장력을 가한 상태로 열처리하여 얻는 섬유이며, 이 열처리 과정 중에 PAN 섬유의 분자쇄에서는 Cyclization, Dehydrogenation 및 산화 반응이 일어나게 된다. 이렇게 제조된 Oxi-PAN 섬유는 탄소섬유의 프리컷(Precursor)로 사용되기도 하고 또한 열안정성이 뛰어나 내염화섬유용으로 사용되기도 한다. (중략)

• Journal of Life Science
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• v.15 no.1 s.68
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• pp.61-65
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• 2005

Using two japonica rice cultivars (Ilpumbyeo and Sanghaehyanghyella), which are distinguishable by the brown planthopper (BHP) resistance maker (R208), a relationship between the BPH resistance gene (Os-Bil) and salt-tolerance was investigated. To do this, changes in the expression level of Os-Bil by the salt stress were quantified by the real-time PCR in the two cultivars, and compared with those in other two indica rice cultivars (Pokkali and IR29). In Ilpumbyeo, the expression level of Os-Bil decreased by the treatments of 50 and 200 mM NaCl in a concentration-dependent manner, and in Sanghaehyanghyella it rather increased slightly at 50 mM but decreased drastically at 200 mM. Comparably, IR29, a salt-sensitive cultivar, showed a reduction of the Os-Bil gene expression after the treatment of 100 mM NaCl, but Pokkali, a salt-tolerance cultivar, rather increased about two times in the level of Os-Bil transcripts. These results suggest that the BPH resistance gene may involve in the difference in the salt-tolerance at least between the two indica rice cultivars.

• Journal of Plant Biotechnology
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• v.42 no.2
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• pp.129-134
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• 2015

In order to compare salt tolerance among potato cultivars (Solanum tuberosum L.), in vitro plants of each cultivar were cultured on the Murashige and Skoog's medium containing different levels of NaCl (0, 75, 150, and 225 mM). The suitable level of NaCl for a comparison of the shoot and root growth between potato cultivars was 75mM. Shoot length and weight were better in 'Dejima', 'Superior', 'Jayoung', and 'Haryeong' than in other cultivars such as 'Goun' and 'Atlantic'. Normal root growth was observed in 'Seohong', 'Superior', and 'Haryeong', while 'Goun', 'Atlantic', 'Dejima', 'Jowon', and 'Chuback' showed no root. Proline contents in all the cultivars increased as affected by NaCl levels, then the increase amount was fewer in the cultivars showed a better growth in both shoot and root than in others showed a poor growth. As a result of this study, 'Superior' and 'Haryeong' were determined as salt tolerant cultivars and therefore using these cultivars it would be possible to potato production at salt arable land such as reclaimed tidal.

• Journal of Applied Biological Chemistry
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• v.60 no.2
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• pp.125-131
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• 2017

Nine strains of high concentrations of salt-tolerant bacteria were isolated from the rhizosphere and rhizoplane of the halophyte plant Suaeda japonica grown in Gochang Buan tidal flat. The isolated bacteria were classified as genera Vibrio (strains JRS-1, -2, -3, -4, and -5, and JRL-1 and -4) and Bacillus (strains JRL-2 and -3) based on the 16S rRNA gene sequence similarity. The optical growth condition for salt concentration was examined on the selected, representative strains. Strain JRS-1 with the closest relative of Vibrio neocaledonicus showed the highest growth rate at the total salt concentration of 6% among the incubation conditions of 3-8% salt concentrations. Strain JRL-2 with the closest relative of Bacillus thuringiensis showed the tendency that growth rate increased with increasing salt concentrations and the maximum growth rate at 7% of the total salt concentration. The isolated bacteria showed salt-resistances to higher salt concentrations than their habitat soils with 3%. In addition, we identified evidences of potentially plant interaction-relevant enzymatic activities, from utilization of some substrates rich in plants, such as triglyceride, ${\rho}$-nitrophenyl-${\alpha}$,$\text\tiny{D}$-glucoside, and ${\rho}$-nitrophenyl-${\beta}$,$\text\tiny{D}$-glucoside.

• Korean Journal of Environmental Agriculture
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• v.17 no.2
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• pp.122-126
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• 1998

This experiment was conducted to verify the responses of major crop species to saline stress.To determine the saline tolerance of crop species, sevral crop species were cultivated under sand-culture system using Hoagland's nutrient solution whit 200mM NaCl. The crop species showing saline tolerance were cotton(Gossypium indicum), maize(Zea mays), barely(Hordeum vulgare), and wheat(Triticum aestivum) but perilla (Perilla frutescens) and leguminous crops, mung bean(Phaseolus radiatus), azuki bean(Phaseolus angularis) and soy bean(Glycin max) showed very por tolerance. One the typical symptom was the darkening of leaf color due to increase of chlorophyll concentration.Among of the plant families, Fabaceae was the most susceptible but crop species belonging to Poaceae were more proper for cultivating on reclaimed tidal land in the course of desalinazation. It was suggrsted that the crop species belonging to Fabaceae, a sensitive family to soil salinity, must be cultivated when the soil salinity decreased below 10ds/m. To know the critical salinity level for crop growth,salinity of saline soil collected from reclaimed tidal land was adjusted from 10.0ds/m tp41.7ds/m with tap water. It was suggested that the ECs of the soil in which the plant height of each crop spicies was reduced to 50% of control plant were 22.6 and 21.7 ds/m in rice, barley, corn, mung bean, and soy bean,respectively.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.5B
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• pp.519-524
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• 2010

This study was carried out to select suitable plants for beach revegetation as a preliminary study for quantifying the effect of decreasing sand movement. After planting some herbal plants in field, monitoring of temporal change of vegetation coverage which was index of the growth rate was conducted. Through literature reviews, 24 candidate plants for beach revegetation were selected, then seven species of them, Peucedanum japonicum Thunb., Dianthus japonicus Thunb. ex Murray, Sedum oryzifolium Makino, Sedum takesimense Nakai, Sedum spectabile Boreau, Farfugium japonicum (L.) Kitam., Aster sphathulifolius Maxim. were picked through salinity tolerance experiments in laboratory. Seven species selected by salinity tolerance experiments and two additional herbal plants, Prunella vulgaris var. lilacina Nakai and Linaria vulgaris Mill., not the candidates, were nine final species which were planted in the beach around Osan port, Uljin, Korea. The changes of vegetation coverage of each species were investigated from photos periodically taken for about a year using image processing methods. As a result of the monitoring, Sedum takesimensei, Dianthus japonicus and Aster sphathulifolius were observed with high coverages during the whole monitoring while Prunella vulgaris var. lilacina and Linaria vulgaris were observed with low coverage during the same period. Consequently, Sedum takesimensei, Dianthus japonicus and Aster sphathulifolius were concluded as the most suitable plants for beach revegetation. Furthur study to quantify the effects of decreasing sand movement by the selected species is needed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.11a
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• pp.133-134
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• 2014

As a previous research, improved durability of concrete by filling capillary pores with waste cooking oil was suggested as a method of controlling carbonation of the concrete replaced high volume of SCMs. on the other hand, the emulsified refined waste cooking oil for better mixing performance had a drawback of reducing air content related with decreasing freeze-thawing resistance. As a solution of this problem, surface applying method was suggested instead of adding in mixing process, and in this research, the performance regarding concrete durability are evaluated comparing emulsified refined cooking oil with water-repelling agent.

• Journal of the Korea Concrete Institute
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• v.19 no.5
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• pp.639-646
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• 2007

This study performed several tests for the durability of the concrete coated with nano synthesis ceramics which do not contain volatile organic compounds harmful to environment. The tests were adhesion test on dry and humid concrete, SEM test, MIP analysis, carbonation, chloride diffusion by electronic facilitation, freezing-thawing resistance, alkaline resistance, and brine resistance test. In the adhesion test on dry and humid concrete, nano synthesis ceramics coating produced the highest results among all the coatings tested. Nano synthesis ceramics adhered solidly on the concrete surface. The adhesive strength seemed to result from the hydrogen bond between nano synthesis ceramics which are inorganic and generated by hydrolysis and re-condensation reaction and the concrete's hydrates such as calcium silicate aluminate or calcium silicate hydrate. SEM test and MIP analysis results show surface structure with finest crevices pore in the nano synthesis ceramics coating applied concretes. In the carbonation, chloride diffusion, and freezing-thawing resistance tests, the concretes with nano synthesis ceramics coating indicated the best results. Based on these test results, further progress in application of nano synthesis ceramics coatings to various concrete structures including costal structures and sewerage arrangements can be expected.