• Title/Summary/Keyword: PP

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A Study on the Synthesis of ACE/PP-g-AN Hybrid Fibers by Irradiation and Separation of Uranium (방사선 중합에 의한 ACF/PP-g-AN 복합섬유의 합성 및 우라늄 분리에 관한 연구)

  • 황택성;황대성;노영창
    • Polymer(Korea)
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    • v.24 no.2
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    • pp.174-181
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    • 2000
  • The ACF/PP-g-AN copolymers were synthesized by the irradiational grafting of acrylonitrile onto ACF/PP hybrid fabric. The synthesis of the ACF/PP-g-AN copolymer was evidenced by the band of -C=N absorption peak at 2250 $cm^{-1}$ / and amidoximation was evidenced by the band of -OH and -NH$_2$ peak at 3450 $cm^{-1}$ / on FT-IR spectrum. The optimal time for the uranium ion adsorption equilibrium on ACF/PP-g-AN copolymers was 8 days and the optimal pH was 8. The adsorption capacities of ACF/PP-g-AN copolymers increased according to the content of amidoxime and were not varied even after more than 10 times of regeneration.

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A Repository Model of Security Environment Contents based on CC (CC 기반의 보안환경 컨텐츠 리파지토리 모델)

  • Choi Sang-Soo;Bang Young-Hwan;Lee Gang-Soo
    • Journal of Digital Contents Society
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    • v.5 no.2
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    • pp.157-162
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    • 2004
  • A development of PP/ST is essential in CC environment. And, the KOREA is expected that PP/STs demand increases explosively by joining to CCRA hereafter. Specially, PP/ST development experience of the KOREA is lacking. So, development of security environment(assume, threat, policy) and security objective contents refer only PP/ST Guide(ISO/IEC PDTR 15446) are very difficult. In this paper, we propose a web service based common security environment and security objective repository model that make developers can run PP/ST creation to be simple. Through proposed model, developers who development experience is lacking are expected to achieve PP/ST development to be simple.

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Surface Modification of Polypropylene Fiber by Plasma Discharge (방전처리에 의한 Polypropylene섬유의 표면개질)

  • 허만우;이창재;강인규;한명호;김삼수;임학상
    • Textile Coloration and Finishing
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    • v.11 no.2
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    • pp.27-37
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    • 1999
  • Polypropylene(PP) films were treated with plasma glow discharge to produce peroxy radicals on the surfaces. The peroxy radicals formed on the PP film surfaces were subsequently used for the graft polymerization of acrylic acid and acrylamide in an aqueous solution by heating, respectively. Introduction of acrylic acid and acrylamide on the PP film could be confirmed by the observation of carbonyl and primary amine absorptions based on carboxylic acid and amide, respectively. And introduction of functional group could be confirmed by weight analysis and ESCA. The water contact angle(90$^{\circ}$) of PP film was constant, irrespective of elapsed time, while plasma-treated and functional monomer-grafted PP films were slowly increased with elapsed time, showing the rearrangement of surface polar groups in air condition. The water contact angle$(90^\circ)$ of PP film was decreased by the plasma treatment$(56^\circ)$ and further decreased by the grafting of acrylic acid$(34^\circ)$ and acrylamide$(37^\circ)$, indicating increased hydrophilicity of the modified surfaces. The water contact angle of plasma-treated PP film increased a little as time elapsing. The half-life periods of surface voltage on acrylic acid-(31sec) and acrylamide-grafted PP(42sec) were significantly decreased when compared to those on PP(950sec) and plasma-treated PP film(241sec). In the experiments using acid, basic and disperse dyes, absorbance and $\Delta{E}$ values of functional monomer-grafted PP films were significantly increased than that of oxygen plasma-treated one.

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Effects of Oxygen Plasma Treatment on the Wettability of Polypropylene Fabrics

  • Kwon, Young Ah
    • Fashion & Textile Research Journal
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    • v.16 no.3
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    • pp.456-461
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    • 2014
  • The objective of this study is to give PP(polypropylene) fabric a good affinity for water. Oxygen plasma was treated to PP fabrics in a commercial glow discharge reactor with different RF power, discharge pressure, and reaction time. The PP fiber surfaces were characterized by the measurement of contact angle and ESCA. A JEOL scanning electron microscope was used to observe the surface morphology of fibers. The spontaneous water uptake amount of PP fabrics was determined by the demand wettability test. To determine the effect of aging on the surface properties of $O_2$ plasma treated PP, all the above measurements of the samples were carried out after 1, 7, 30, 60, and 150 days. The results are as follows. The PP fiber surfaces treated by $O_2$ plasma treatment have a chemical composition that consisted of various oxygen containing polar groups. Consequently, the contact angles of the treated PP fibers decreased, which improved the water uptake rate of PP fabrics. Surface roughness of the treated PP affected the fabric wettabiity as well. Wettability of the treated PP decreased and leveled off with aging. The $O_2$ plasma treatment is a simple and effective method to increase the water uptake rate of PP fabrics.

Rule-based CC/PP profiling method in ubiquitous environment (유비쿼터스 환경을 위한 규칙 기반 CC/PP 프로파일 생성 방법)

  • Song Jae-Kyoung;Oh Sang-Hyun;Byun Yung-Cheol;Lee Sang-Joon
    • Proceedings of the Korea Contents Association Conference
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    • 2005.11a
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    • pp.539-542
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    • 2005
  • In the ubiquitous computing environment, service providers should able to deliver their services to various devices, such as PDA Smart Phone, Telematics devices. For this, W3C announced 'Composite Capabilities/Preference Profile (CC/PP) Standard' for delivery-context description. But at present, only a small number of mobile phone supports the CC/PP standard, most of contents servers do not support the CC/PP profiles. In this paper, a rule-based CC/PP profiling method in ubiquitous environment is developed. A rule-based profiles are generated by analyzing request headers which are received from various ubiquitous devices. Service providers can use these profiles to provide optimized services to the various devices which have different capabilities.

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Chemical Modification of Isotactic Polypropylene by Melt Blending

  • Kim, Jun-Young;Seo, Eun-Su;Park, Dae-Soon;Park, Kwang-Min;Kang, Seong-Wook;Lee, Chang-Hyung;Kim, Seong-Hum
    • Fibers and Polymers
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    • v.4 no.3
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    • pp.107-113
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    • 2003
  • The branched polypropylene (b-PP) was prepared by melt blending process with initiator, antioxidant, and functional monomers to improve the melt strength through the melt grafting. The melt flow index (MFI) of the b-PP was increased with increasing the initiator content. On the introduction of the alkylamine as the branching agents the MFI of the b-PP was increased, while that of the b-PP with the pentaerythritol triacrylate (PT) was decreased. It may be caused by the chain scission of the i-PP backbone due to the reduced thermal stability of the i-PP on the melt blending. The MFI of the b-PP without the antioxidant was increased due to the chain scission occurred during the melt processing, while on the introduction of the antioxidant, the MFI of the b-PP was decreased. The crystallization temperature of the b-PP was higher than that of PP, which was attributed to the branched chain structure. It was found that the PT was the most effective functional monomers for enhancing the melt properties of the b-PP.

Effect of Ar+ Ion Irradiation of Polymeric Fiber on Interface and Mechanical Properties of Cementitious Composites

  • Seong, Jin-Wook;Lee, Seung-Hun;Kim, Ki-Hwan;Beag, Young-Whoan;Koh, Seok-Keun;Yoon, Ki-Hyun
    • Journal of the Korean Ceramic Society
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    • v.41 no.6
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    • pp.430-434
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    • 2004
  • The values of fracture energy and mechanical flexural strength of Fiber Reinforced Cement (FRC) with polypropylene (PP) fiber modified by Ion Assisted Reaction (JAR), by which functional groups were grafted on the surface of PP fiber, was improved about 2 times as those of fracture energy and flexural strength of cement reinforced by untreated PP fiber. PP fiber was irradiated in O$_2$ environment by Ar$\^$+/ ion. The contact angle of PP treated by IAR decreased largely when compared with untreated PP. From this result, we expected that surface energy and interfacial adhesion force of treated PP fiber increased. The strain hardening occurred in the strain-stress curve of FRC including PP treated by IAR when compared with that of FRC with untreated PP. These enhanced mechanical properties might be due to strong interaction between hydrophilic group on modified PP fiber and hydroxyl group in cement matrix. This hydrophilic group on surface modified PP fiber was confirmed by XPS analysis. We clearly observed hydration products that were fixed at modified PP fiber due to the strong adhesion force of interface in cement reinforced modified PP by SEM (Scanning Electron Microscopy) study.

Paralytic Peptide Binding Protein (PP-BP) Gene Expression During Egg Diapause and Its Multi-Gene Organization in the Silkworm Bombyx mori

  • Sirigineedi, Sasibhushan;Murthy, Geetha N.;Rao, Guruprasada;Ponnuvel, Kangayam M.
    • International Journal of Industrial Entomology and Biomaterials
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    • v.26 no.1
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    • pp.31-40
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    • 2013
  • Paralytic peptide binding proteins (PP-BP) are 30KP proteins that show similarity to ENF binding proteins. The ENF-BP act as active regulators of ENF peptides. ENF peptides are multifunctional insect cytokines. The comparison of gene expression in diapause induced and non-diapause eggs at different time intervals after oviposition showed an upregulation of PP at 18h as well as PP-BP at 12 and 18h after oviposition along with few other genes. The current study has been taken up to investigate the role of PP as well as PP-BP in diapause induction in polyvoltine silkworms and to study the multigene organization of PP-BP in the Bombyx mori genome. The tissue specific expression analysis revealed that, PP-BP is highly expressed in fat body followed by egg and brain while no expression was observed in midgut. The expression levels of PP and PP-BP in diapause and non-diapause eggs from 0h to 48h after oviposition, validated through realtime PCR revealed that PP is highly expressed at 18 and 24h while PP-BP expression is higher at 12 and 18h time intervals suggesting their possible role in diapause induction. The whole genome survey of the PP-BP paralogous sequences revealed a total of 46 B. mori PP-BP homologs that are classified into 3 categories viz., ENF-BP, Typical 30KPs and serine/threonine rich 30KPs. These paralogous sequences are distributed on chromosomes 7, 20, 22 and 24, all 30KP and S/T rich 30KP proteins are present in the same locus of chromosome 20.

Identification of Calcium/Calmodulin-Dependent Phosphatase as the Dephosphorylating Enzyme of IgE-Dependent Histamine-Releasing Factor in RBL-2H3 (RBL-2H3 세포에서 IgE-depnedent Histamine-releasing Factor의 탈인산화 효소에 관한 연구)

  • Hwang Sun-Ok;Lee Kyunglim
    • Microbiology and Biotechnology Letters
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    • v.33 no.3
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    • pp.189-193
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    • 2005
  • IgE-dependent histamine-releasing factor(HRF) was initially described as a secretagogue for secretion of histamine from IgE+ basophils from a subset of allergic donors. Previously, we identified that S98 residue of HRF was phosphorylated using anti-HRFpS98 antibody which specifically recognizes the phosphorylated serine residue of HRF and HRFS98A mutant construct. In vitro kinase assay, only wild type HRF was phosphorylated by PKC, and S98A HRF was not affected by PKC. In this study, we attempted to characterize the phosphatase which specifically dephosphorylates HRF by immunoprecipitation and pull-down assay. In RBL-2H3 cells, HRF interacted only with calcineurin (also called as PP2B, calcium/calmodulin-dependent phosphatase) but not with PP1 or PP2A. The results suggest that HRF is most likely dephosphory-lated by calcineurin.

Socio-economic disparity in food consumption among young children in eight South Asian and Southeast Asian countries

  • Kang, Yunhee;Park, Chulwoo;Young, Anna Marie Pacheco;Kim, Jihye
    • Nutrition Research and Practice
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    • v.16 no.4
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    • pp.489-504
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    • 2022
  • BACKGROUND/OBJECTIVES: This study examined socio-economic differences in diverse food consumption among children 6-23 months of age in South Asia and Southeast Asian countries. SUBJECTS/METHODS: Data from Demographic and Health Surveys in four countries in South Asia (n = 15,749) and four countries in Southeast Asia (n = 10,789) were used. Survey-design adjusted proportions were estimated for the following 10 food items: grains, legumes, dark green leafy vegetables (DGLV), vitamin A-rich fruits, vitamin A-rich vegetables, other fruits and vegetables (OFV), fish, meat, dairy, and eggs. An equity gap was defined as an arithmetic difference in the proportion of each food item consumed in the past 24-hours between the wealthiest and lowest quintiles and between rural and urban areas, denoted by percentage points (pp). RESULTS: The consumption of most of the 10 food items was higher in the wealthiest quintiles and urban areas across eight countries. The size of equity gaps was greater in Southeast Asia than in South Asia, particularly for vitamin A-rich fruits (3.3-30.0 pp vs. 0.3-19.6 pp), vitamin A-rich vegetables (12.1-26.7 pp vs. 2.4-5.9 pp), meat (17.7-33.4 pp vs. 3.4-13.4 pp), and dairy (14.7-32.5 pp vs. 3.3-11.4 pp). However, the size of equity gap in egg consumption was greater in Southeast Asia than South Asia (11.2-19.8 pp vs. 11.0-26.7 pp). Relatively narrower gaps were seen in the consumption of grains (0.3-12.9 pp), DGLV (0.6-12.4 pp), and fish (0.1-16.8 pp) across all countries. CONCLUSIONS: Equity gaps in food consumption differed by socio-economic status and region. Reducing equity gaps in nutrient-rich foods and utilizing regionally available food resources may increase child dietary quality.