• Title/Summary/Keyword: Functional Resistance

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Electrochemical Characteristics of Reforming Activated Carbon with Nitrogenous Functional Group for Electric Double Layer Capacitor (전기이중층 커패시터용 질소성 작용기를 이용한 개질 활성탄의 전기화학적 특성)

  • Yang, Jeong-Jin;Choi, Young-Joo;Kim, Han-Joo;Yuk, Young-Jae;Park, Soo-Gil
    • Journal of the Korean Electrochemical Society
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    • v.16 no.2
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    • pp.65-69
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    • 2013
  • In order to improve capacitance of activated carbon for electric double layer capacitors, peptide bond was induced on the surface of the activated carbon by urea. Urea induced activated carbon has been stabilized through carbonization. Electrochemical characteristics was observed by cyclic voltammetry for specific capacitance, electrochemical impedance spectroscope for measuring resistance and charge-discharge for testing the cyclic ability. In the result, specific capacitance is increased about 22.9% than the activated carbon. And it shows excellent cycle performance and decreasing resistance with the introduction of nitrogen functional groups.

Preparation and Super-Water-Absorbency of Poly(sodium acrylate-co-acrylamide-co-2-hydroxyethyl acrylate) (Poly(sodium acrylate-co-acrylamide-co-2-hydroxyethyl acrylate)의 제조와 고흡수 특성)

  • Zhang Yuhong;Deng Min;He Peixin
    • Polymer(Korea)
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    • v.30 no.4
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    • pp.286-292
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    • 2006
  • Super water-absorbent resins were prepared by inverse suspension copolymerization of sodium acrylate, acrylamide and 2-hydroxyethyl acrylate using N, N'-methylene-bis-acrylamide as cross-linker. For the suspension copolymerization, monohexadecyl phosphate was employed as the dispersing agent, cyclohexane as the dispersing medium and potassium persulfate as the initiator. The dependence of water-absorption capacity on the amount of crosslinking agent, oil/water ratio, degree of neutralization and the composition of the copolymer were systematically investigated. Furthermore, the swelling kinetics of the super water-absorbent copolymer was carried out. The absorption of the resins is more than 1800 g/g for deionized water and 100 g/g for 0.9% NaCl solution, respectively. The copolymers showed an increased salt resistance and enhanced water retention of soil.

Effect of Coagulant Type on the Silica Dispersion and Properties of Functionalized RAFT ESBR Silica Wet Masterbatch

  • Kim, Woong;Ryu, Gyeongchan;Hwang, Kiwon;Song, Sanghoon;Kim, Wonho
    • Elastomers and Composites
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    • v.55 no.3
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    • pp.167-175
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    • 2020
  • Various studies have been conducted to improve silica dispersion of silica filled tire tread compounds; among them, silica wet masterbatch (WMB) technology is known to be suitable for manufacturing silica filled compounds that have high silica content and high dispersibility. Till now, the WMB study is focused on the natural rubber (NR) or emulsion styrene-butadiene rubber (ESBR) that does not have a silica-affinity functional group, and a study of NR or ESBR having a silica-affinity functional group is still not well known. Unlike the dry masterbatch technology, the WMB technology can solve the problems associated with the high Mooney viscosity when applied to silica-friendly rubber. However, a coagulant suitable for each functional group has not yet been determined. Therefore, in this study, different coagulant applied silica WMB was prepared by applying calcium chloride, sulfuric acid, acetic acid, and propionic acid by using a carboxyl group functionalized reversible addition fragmentation chain transfer ESBR. The evaluation of the WMB compounds revealed that the calcium chloride added WMB compound showed excellent silica dispersion, abrasion resistance, and rolling resistance.

Properties of Water-based Paint mixed with Photocatalyst for Indoor Air Quality Improvement (실내 공기질 개선을 위한 광촉매를 혼입한 수성도료의 특성)

  • Choi, Byung-Cheol;Park, Chae-Wool;Kyoung, In-Su;Lee, Sang-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2020.06a
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    • pp.29-30
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    • 2020
  • As the modern society enters, the building becomes sealed and the public's interest in the environment increases, so the interest in indoor air pollution increases and the environmental pollution is raised as an important issue not only outdoors but also indoors. In addition, the emergence of sick house syndrome (SHS) has increased the interest in formaldehyde and is a cause of deteriorating indoor air quality. Accordingly, this study prepared a functional paint by incorporating a photocatalyst in an aqueous paint, and conducted formaldehyde adsorption experiments and functional evaluation. As a result of the experiment, as the photocatalyst was added, the formaldehyde adsorption performance tended to increase. In addition, as a result of measuring the impact resistance and alkali resistance according to the KS standard, there is no difference in residual cracks and cracks between the water-based paint without the photocatalyst and the water-based paint with the photocatalyst added. Therefore, it is considered that the water-based paint added with a photocatalyst can improve the indoor air quality by adsorbing formaldehyde and can be used as a functional paint because the functionality is not different from that of a general water-based paint.

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Toward Functional Genomics of Plant-Pathogen Interactions: Isolation and Analysis of Defense-related Genes of Rot Pepper Expressed During Resistance Against Pathogen

  • Park, Do-Il;Lee, Sang-Hyeob
    • The Plant Pathology Journal
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    • v.18 no.2
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    • pp.63-67
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    • 2002
  • To understand plant-pathogen interactions, a complete set of hot pepper genes differentially expressed against pathogen attack was isolated. As an initial step, hundreds of differentially expressed cDNAS were isolated from hot pepper leaves showing non-host resistance against bacterial plant pathogens (Xanthomonas campestris pv. glycines and Pseudomonas syringae pv. syringae) using differential display reverse transcription polymerase chain reaction (DDDRT-PCR) technique. Reverse Northern and Northern blot analyses revealed that 50% of those genes were differentially expressed in pepper loaves during non-host resistance response. Among them, independent genes without redundancy were micro-arrayed for further analysis. Random EST sequence database were also generated from various CDNA libraries including pepper tissue specific libraries and leaves showing non-host hypersensitive response against X. campestris pv. glycines. As a primary stage, thousands of cDNA clones were sequenced and EST data were analyzed. These clones are being spotted on glass slide to study the expression profiling. Results of this study may further broaden knowledge on plant-pathogen interactions.

Excellent Seam Weldable Nano-Composite Coated Zn-Ni Plating Steels for Automotive Fuel Tank

  • Jo, Du-Hwan;Yun, Sang-Man;Park, Kee-Cheol;Kim, Myung-Soo;Kim, Jong-Sang
    • Corrosion Science and Technology
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    • v.18 no.1
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    • pp.16-23
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    • 2019
  • Steels for automotive fuel tank require unique properties such as corrosion resistance for fuel, welding for joining, forming for press, and painting for exterior. Recently, automakers have been requiring excellent seam weldable steels to enhance manufacturing productivity of fuel tank. Thus, POSCO developed a new type of functional steels coated with nano-composite thin layer on Zn-Ni plating steels. The nano-composite coating solution was prepared by mechanical fine dispersion of solutions consisting of polymeric resin and nano-composite materials in aqueous media. The composite solution was coated on the plating steel surface by using roll coater and cured through induction furnace. These new developed plating steels were evaluated for quality performances such as seam and spot weldability, press formability, and corrosion resistance. These new functional steels coated with nano-composite layer exhibited excellent seam weldability and press formability. Detailed discussion of coating solution and experimental results suggest that nano-sized composite dispersion as coating layer plays a key role in enhancing the quality performance.

A New Medium Maturing and High Quality Rice Variety with Lodging and Disease Resistance, 'Haeoreumi' (중생 고품질 내도복 내병성 벼 품종 '해오르미')

  • Kim, Jeong-Il;Park, No-Bong;Park, Dong-Soo;Lee, Ji-Yoon;Yeo, Un-Sang;Chang, Jae-Ki;Kang, Jung-Hun;Oh, Byeong-Geun;Kwon, Oh-Deog;Kwak, Do-Yeon;Lee, Jong-Hee;Yi, Gihwan;Kim, Chun-Song;Song, You-Cheon;Cho, Jun-Hyun;Nam, Min-Hee;Choung, Jin-Il;Shin, Mun-Sik;Jeon, Myeong-Gi;Yang, Sae-Jun;Kang, Hang-Weon;Ahn, Jin-Gon;Kim, Jae-Kyu
    • Korean Journal of Breeding Science
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    • v.42 no.6
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    • pp.638-644
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    • 2010
  • A new rice variety 'Haeoreumi' is a japonica rice (Oryza sativa L.) with lodging tolerance, resistance to rice stripe virus (RSV) and bacterial leaf blight (BLB), and high grain quality. It was developed by the rice breeding team of Yeongdeog Substation, National Institute of Crop Science (NICS), RDA in 2008. This variety was derived from a cross between 'Milyang165' with good grain quality and lodging resistance, and 'Haepyeongbyeo' with wind tolerance in winter season of 2000/2001. A promising line, YR22375-B-B-1, selected by pedigree breeding method, was designated as the name of 'Yeongdeog46' in 2005. 'Yeongdeog46' was released as the name of 'Haeoreumi' in 2008 after the local adaptability test that was carried out at nine locations from 2006 to 2008. 'Haeoreumi' has 74 cm short culm length as and medium maturating growth duration. This variety showed resistance to $K_1,\;K_2$, and $K_3$ races of bacterial blight, and stripe virus and moderate resistant to leaf blast disease with durable resistance, and also has tolerance to unfavorable environment such as cold, dry and cold salty wind. 'Haeoreumi' has translucent and clear milled rice kernel without white core and white belly rice, and good eating quality as a result of panel test. The yield potential of 'Haeoreumi' in milled rice is about 5.58MT/ha at ordinary fertilizer level of local adaptability test. This cultivar would be adaptable to Middle plain, mid-west costal area, and east-south coastal area.

Compaction Characteristics of Multi-cropping Paddy Soils in South-eastern Part of Korea (우리나라 동남부 다모작 논토양의 경반화 특성)

  • Yun, Eul-Soo;Jung, Ki-Yeul;Park, Ki-Do;Sonn, Yeon-Kyu;Park, Chang-Yeong;Hwang, Jae-Bog;Nam, Min-Hee
    • Korean Journal of Soil Science and Fertilizer
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    • v.44 no.5
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    • pp.688-695
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    • 2011
  • This study was carried out for some survey about soil compaction in the multi-cropping system of paddy field. Investigated sites were 90 farmer's fields in south-eastern part of Korea. The tillage practices season was different according to cropping system of paddy; in spring for mono rice cultivation and in autumn for the multi-cropping field. The average tillage depth in investigated sites was about 25 cm, however, it is different between the farmer's tillage practices and soil characteristics. It is high correlation to tillage deep and minimum resistance of penetration. The reaching soil deep to maximum resistance of penetration was about 27 cm, and average penetration resistance of the deep is 1.8~2.0 MPa for moderately fine-textured soils and more than 3.0 MPa for moderately coarse-textured soils. The difference of penetration resistance between cultivating and compacted layer was in order to sandy loam > clayey loam > clayey, and the difference was lesser in poorly drained soils than somewhat poorly ones. In the rice mono cropping field, the maximum resistance in no-tillage for 15 years was 1.18~1.25 Mpa at 20~25 cm in soil deep, however, the resistance of field with every year tillage practices was 2.03~2.21 Mpa. In the extremely compacted sandy loam textured soils, the penetration resistance at 30 cm in soil depth was drastically reduced by the subsoil from 5.2 Mpa to 3.2 Mpa, and the watermelon root in plastic film house was deep elongated.

New Polytriazoleimides with High Thermal and Chemical Stabilities

  • E, Yanpeng;Wan, Liqiang;Li, Yujing;Huang, Farong;Du, Lei
    • Bulletin of the Korean Chemical Society
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    • v.33 no.7
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    • pp.2193-2199
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    • 2012
  • A series of novel polytriazoleimides were prepared from various aromatic dianhydrides and a new kind of 1,2,3-triazole-containing aromatic diamine synthesized by the Cu (I)-catalyzed 1,3-dipolar cycloaddition reaction in DMAc, and characterized by FT-IR, $^1H$-NMR, XRD, DSC and TGA techniques. The results show the polytriazoleimides are soluble in most of strong polar solvents and have inherent viscosity values of 0.51-0.62 dL/g(DMAc). The polytriazoleimide films exhibit a tensile strength of 62.3-104.5 MPa and an elongation at breakage of 4.0-8.1%, a glass transition temperature ($T_g$) of $257-275^{\circ}C$, a decomposition temperature (at 5% weight loss) of $350-401^{\circ}C$ in $N_2$ atmosphere, and a dielectric constant of 2.47-3.01 at 10 MHz, which depend on the structure of the polymers. The polytriazoleimides perform good resistance to acid and alkali solution.