• 한국응용과학기술학회지
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• 제20권4호
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• pp.341-345
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• 2003

Organic acid salt of fatty polyamide (DDDT) and acrylate of fatty carbamide (DDTCA) were synthesized as a main component for the softener. O/W type non-ionic softener (NSC) was prepared by blending DDDT and DDTCA with beef tallow, lanolin anhydride. polyoxyethylene(7) stearyl ether, and polyoxyethylene(50) oleyl ether. After treatment of NSC to all cotton fabrics, the physical properties such as tear strength, crease recovery, and flexing abrasion resistance were measured. As a result of the measurement, NSC was proved to be durable non-ionic softener with good softness.

• 한국구조물진단유지관리공학회 논문집
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• 제12권6호
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• pp.249-256
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• 2008

해양콘크리트 구조물의 내구성은 염분의 침투와 확산에 의해 심하게 저하한다. 이로 인해 많은 연구자들이 해양구조물에 대한 내구성을 향상시키기 위한 연구를 수행하여 왔다. 이 연구에서는 광물질 혼화재, 코팅철근, 부식억제제를 사용한 휨 부재에 대하여 4점 휨 시험을 수행함으로써 휨 거동을 비교 평가하고 해양구조물로의 적용성을 검토하였다. 결과에 따르면, 광물질 혼화재와 부식억제제는 초기균열 안전성과 휨 저항에 효율적인 것으로 나타났다. 내구성 재료를 사용하여도 동일 휨 모멘트 구간에서의 인장철근 응력 변화는 적고 부재도 안정된 거동을 보인다. 또한, 내구성 재료를 사용한 부재의 균열간격도 크지 않게 나타났다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1996년도 봄 학술발표회 논문집
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• pp.71-76
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• 1996

Recently, large scale concrete structures exposed to severe environment are increasingly built in various locations. The corrosion may affect severely the durability and service life of such a concrete structure. It is, therefore, necessary to develop durable concrete to enhance the corrosion resistance. The corrosion resistance of concrete can be identified through accelerated corrosion test. The purpose of the present paper is, therefore, to devise a reasonable and accurate method to predict the amount of corrosion of reinforcing steels. The proposed method which is basically based on the concept of Faraday's Law, determines the corroded amount of a re-bar according to accelerated corrosion time. The corrosion is accelerated by employing the potentiometric corrosion test arrangement. The effects of admixtures in concrete including fly ash and silica fume have been also studied to explore the relative corrosion resistance of concrete.

• Journal of Crop Science and Biotechnology
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• 제10권1호
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• pp.3-7
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• 2007

Classification of blast resistance type of 129 Korean rice cultivars was carried out based on reaction pattern to 10 Japanese blast pathogen isolates(Pyricularia oryzae). The cultivars were divided into 11 groups based on the presumed resistance genes as follows; Pia type(19 cultivars), Pita-2 type(4), Pik type(3), Pib type(5), Piz type(11), Pik-s type(8), Pik and Pii type(4), Pia and Pita type(8), Pia and Pik type(6), Pita, Pik and Pii type(4) and no-grouping type(57). These results would provide important information to rice breeding for durable and broad resistance to rice blast.

• Advances in nano research
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• 제17권2호
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• pp.157-165
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• 2024

This paper discusses the importance of carbon nanotubes (CNTs) in enhancing performance and resistance of tennis rackets with the application of nanotechnology. This paper discusses how nanomaterials work toward making the equipment lighter, stronger, and more durable by combining CNTs with composite materials in Tennis Rackets. Distinctive properties of the CNTs, such as the very high strength-to-weight ratio and exceptional mechanical resilience, have been exploited in racket performance optimization for better power transmission, increased control on shots, and improved durability. Resistance to wear and tear is discussed in terms of the life of a CNT-enhanced tennis racket and its continued performance with time. The findings imply that the CNTs increase the security and overall performance of tennis rackets, hence promising further innovation in sports technology equipment and the various performances expected from users.

• 한국응용곤충학회지
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• 제31권3호
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• pp.256-275
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• 1992

Insects are among the most important abiotic and biotic constraints to rice production. National rice research programs are in various stages in the development and implementation of integrated pest management (IPM) stratagies for rice insect control. Among the various control tactics, insect resistant cultivars are sought as the major tactic in rice IPM. Through the activities of interdisciplinary teams of scientists significant progress has been made in the development and release of insect resistant cultivars to farmers. Because of its compatibility with other control tactics insect resistance has proven to fit well into the IPM approach to rice insect control agents and minimize the need for insecticide applications. The development of biotypes which overcome the resistance in rice plants has been a significant constraint in the breeding of rice for resistance to insects. Most notable examples in Asia are the green leafhopper, Nephotettix virescens, brown planthopper, Nilaparvata lygens and the Asian rice gall midge, Orseolia oryzae. The current breeding stratege is to develop rice cultivars with durable resistance on which virulent biotypes cannot adapt. In spite of the significant progress made in the breeding of insect resistant cultivars there are still numerous important rice insect species for which host plant resistance as a control tactic has not been fully utilized. Advances in biotechnology provide promise of solving some of the problems that have limited the use of host plant resistance as a major tactic in the integrated management of rice insect pests.

• 한국도로학회논문집
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• 제17권2호
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• pp.47-53
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• 2015

PURPOSES: The scaling of a concrete surface caused by the combined effects of frost and de-icing salts is one of the main reasons for the need to repair transportation infrastructures in cold-climate regions. This study describes the results of attempts to determine the scaling resistance of concrete incorporating mineral admixtures such as fly ash, GGBFS, and silica fume, and subjected to the actions of frost and salt. METHODS : Conventionally, to evaluate the fundamental properties of concrete, flexural and compressive strength measurements are regularly performed. Based on the ASTM C 672 standard, concrete is subjected to 2%, 4%, and 8% $CaCl_2$ salt solutions along with repeated sets of 50 freeze/thaw cycles, and the scaling resistance was evaluated based on the mass of the scale and a visual examination. RESULTS : It was observed that silica fume is very effective in enhancing the scaling resistance of concrete. Meanwhile, concrete incorporating GGBFS exhibited poor resistance to scaling, especially in the first ten freeze/thaw cycles. However, fly ash concrete generally exhibited the maximum amount of damage as a result of the frost-salt attack, regardless of the concentrations of the solutions. CONCLUSIONS: It can be concluded that the scaling resistance of concrete is highly dependent on the type of the mineral admixture used in the concrete. Therefore, to provide a durable concrete pavement for use in cold-climate regions, the selection of a suitable binder is essential.

• 콘크리트학회논문집
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• 제16권2호
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• pp.269-275
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• 2004

Factorial design method is applied to investigate the effects of various factors simultaneously rather than to conduct a series of single-factor experiment. As the results, frost resistance of the concrete specimens, in both W/C ratio of 0.28 and 0.35, was highly affected by the type of coarse aggregate that is, andesite produced more durable concrete than the limestone. Durability factor of the specimens, with W/C ratio of 0.28, which were demolded after I day and transferred to the curing room was higher than those demolded after 2 days. This stated the efficiency of the high early curing in high strength concrete.

• Fibers and Polymers
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• 제2권4호
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• pp.184-189
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• 2001

Continuous photografting/crosslinking of polyethyleneglycol dimethacrylate oligomers onto cotton using a water-soluble benzophenone photoinitiator was investigated. Photografting increased with increasing irradiation dose, oligomer concentration and photoinitiator concentration. Maximum grafting efficiency of DM 400 and 600 were 83% and 79%, respectively. the photografting increased the wrinkle resistance of cotton implying surface crosslinking of cotton. bothsurface crosslinking and bulk crosslinking of cotton were accomplished via dual curing of a mixed formulation containing both a thermally curable component (BTCCA/SHP) and a UV-curable component. The wrinkle resistance of the crosslinked cotton was found to be higher when cured by thermal curing due to the facile post-polymerization of the UV active component. The presence of crosslinks in the dually crosslinked cotton was verified with FT-IR and thermogravimetric analysis.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.65-67
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• 2014

There are many elastomeric joint sealant applications in construction such as structural glazing, weatherproofing and insulating glass fabrication etc. Each sealant joints require unique durability functions to perform well through building life cycle. Elastomeric joints in bathroom and kitchen is one of areas which require durable sealing. In this application, anti fungal durability is proprietary function of sealant during building life cycle. Premature failure of anti fungus resistance of sealant is putting big stresses to general contractor as well as the inhabitants due to costly rework and poor sanitation. Accordingly, when chemists design a product, they must take into account various parameters not only formulation components also test conditions in order to have long term fungal durability. This paper reviews several biocide options with various industry standards for fungus resistance performance to suggest making new test method for construction sealant industry.