• Title/Summary/Keyword: Natural Property

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On the asymptotic-norming property and the mazur intersection property

  • Cho, Sung-Jin
    • Journal of the Korean Mathematical Society
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    • v.32 no.3
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    • pp.583-591
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    • 1995
  • Unless otherwise stated, we always assume that X is a Banach space, and $1 < p, q < \infty with \frac{p}{1}+\frac{q}{1} = 1$. We use S(X) and B(X) to denote the unit sphere and the unit ball in X respectively.

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Dynamic Mechanical and Morphological Properties of Natural Rubber Vulcanizates Containing Fillers

  • Lee, Hae Gil;Park, Chan Young
    • Elastomers and Composites
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    • v.51 no.3
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    • pp.218-225
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    • 2016
  • In order to examine correlation between silane coupling agent and activator which affects the physical properties of silica filled natural rubber compound, such as heat buildup, rebound property, dynamic mechanical and morphological properties were measured. With incorporation of silane coupling agent, $tan{\delta}$ at $0^{\circ}C$ was increased and at $60^{\circ}C$ was decreased, which resulted in improving of wet grip and rolling resistance. When silane coupling agent which is corresponding to 8~10% of silica was used, most favorable heat build up and $tan{\delta}$ was obtained. And also when activator was used, dispersibility of silica was improved as a result of reduction of reaggregation of silica.

Study on the optical properties of ZnS and its natural oxide by spectroscopic ellipsometry

  • Kim, T. J.;Kim, Y. D.;Park, Y. D.
    • Journal of Korean Vacuum Science & Technology
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    • v.5 no.2
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    • pp.52-55
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    • 2001
  • We report best dielectric function of ZnS by spectroscopic ellipsometry in the 3.7 - 6.0 eV photon energy range at room temperature. Using proper wet chemical etching procedure, natural overlayer was removed to obtain the pure dielectric function of ZnS, which had a higher <$\xi$$_2$> value at the El band gap peak than that previously reported. We also determined the dielectric property of the natural overlayer on ZnS by following the evolution of <$\xi$$_2$> with chemical etching. We found that the optical property of the overlayer was well described by amorphous semiconductor model.

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The Chemical Structure and the Dyeability of Yellow Natural Dyestuff (황색계 천연염료의 화학구조 및 염색성)

  • Cha, Min-Kyoung;Lee, Mun-Soo;Park, Joo-Hyuk;Kwon, Yoon-Jung
    • Fashion & Textile Research Journal
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    • v.8 no.2
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    • pp.233-238
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    • 2006
  • This research confirmed the chemical structure of Curcumine and Carthamin pigments whose pigments were separated and refined from the Curcuma longa and Carthamus Tinctorious which were natural dye using FT-IR, HPLC and so on. The cotton and the silk fabrics were dyed using a main pigment and then this research obtained the conclusion as it follows. The curcumine, the main pigment of Curcuma longa extracted from the mixed solvent of acetic anhydride and methanol ($CH_3OH$), had the maximum absorption wavelength at 504.0 nm and was confirmed as yellow natural pigment. The Carthamin, the main pigment of Carthamus Tinctorious extracted from the mixed solvent of dichloromethane and methanol, had the maximum absorption wavelength at 420.0nm. This pigment was confirmed as yellow natural pigment. The dyeing property of the main pigment about the silk fabrics was superior to that about the cotton in both the Curcuma longa and Carthamus Tinctorious, and the dyeing property of Carthamus Tinctorious was superior to that of Curcuma longa.

Preparation of Natural Chemicals Intercalated Aminoclay via One-pot Synthesis and its Antimicrobial Property (One-pot 합성을 통해 천연 화합물이 삽입된 아미노클레이 제조 및 항균성 연구)

  • Kim, Seong Yeol;Choi, Yoo-Sung
    • Applied Chemistry for Engineering
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    • v.28 no.5
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    • pp.495-500
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    • 2017
  • In this study, we synthesized the aminoclay (AC) with magnesium ions and 3-aminopropyl triethoxysilane (APTES). At the same time, propolis intercalated aminoclay (PIAC) and coptis extract intercalated aminoclay (CIAC) were synthesized by intercalating natural chemicals between clay sheets. Clay synthesis and natural chemical intercalation were confirmed through SEM, particle size analyze, FT-IR, TGA and XRD. In particular, the characterization of intercalation of natural chemicals was determined by analyzing the interlayer distance from XRD data. The antimicrobial property of PIAC and CIAC was checked by minimum inhibitory concentration (MIC) test and increased compared with that of the pristine aminoclay (AC).

A GENERALIZATION OF THE NILPOTENT SPACE AND ITS APPLICATION

  • Han, Sang-Eon
    • Bulletin of the Korean Mathematical Society
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    • v.38 no.4
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    • pp.787-795
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    • 2001
  • For the generalized nilpotent spaces, e.g. the locally nilpotent space, the residually locally nilpotent space and the space satisfying the condition ($T^{*}$) or ($T^{**}$), we find the pullback property of them. Furthermore we investigate some fiber properties of the space satisfying the condition ($T^{*}$) or ($T^{**}$), especially locally nilpotent space.

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Effect of Electron Beam Irradiation on the Interfacial and Thermal Properties of Henequen/Phenolic Biocomposites

  • Pang, Yansong;Yoon, Sung Bong;Seo, Jeong Min;Han, Seong Ok;Cho, Donghwan
    • Journal of Adhesion and Interface
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    • v.6 no.4
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    • pp.12-17
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    • 2005
  • Natural fiber/phenolic biocomposites with chopped henequen fibers treated at various levels of electron beam irradiation (EBI) were made by means of a matched-die compression molding method. The interfacial property was explored in terms of interfacial shear strength measured by a single fiber microbonding test. The thermal properties were studied in terms of storage modulus, tan ${\delta}$, thermal expansion and thermal stability measured by dynamic mechanical analysis, thermomechanical analysis and thermogravimetric analysis, respectively. The result showed that the interfacial and thermal properties depend on the treatment level of EBI done to the henequen fiber surfaces. The present result also demonstrates that 10 kGy EBI is most preferable to physically modify the henequen fiber surfaces and then to improve the interfacial property of the biocomposite, supporting earlier results studied with henequen/poly (butylene succinate) and henequen/unsaturated polyester biocomposites.

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An analysis of natural products patents (천연물 신약 특허 동향 분석)

  • Han, Yoo-Jin;Park, Sunju
    • Journal of Society of Preventive Korean Medicine
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    • v.20 no.2
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    • pp.77-86
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    • 2016
  • Objectives : This study aims to investigate the current situation of domestic patents in Korea on natural products and to provide directions for developing and applying herbal medicinal products by in-depth analyses. Methods : Combinations of words, such as "A61K" or "A61P", "herb" or "Korean medicinal herb" or "Korean medicine" or "traditional" or "natural" or "$botanic^*$" or "China", and "medicine" or "treatment" or "prevention" or "improvement", were used to search patents in the World Intellectual Property Service (WIPS) database. Three methods were applied to analyze natural products patents. First, the number of patent registrations was sorted by year. Second, the assignees were analyzed by count and country of origin. Finally, cluster map analysis was conducted to explore frequently emerging words in natural products and the relationship amongst those words to treat corresponding diseases/technologies. Results : Results showed that, first, the total number of patents had been increasing. Among the patents, 76.4% were registered by domestic institutes/companies, and 23.6% by foreign institutes/companies. Second, USA, Japan, and China possess a considerable number of Korean patents and, therefore, domestic institutes/companies can seek joint technological development opportunities with their counterparts from those countries in the future. Finally, a total of four clusters were identified by cluster map analysis. Each of the clusters includes natural products related to diseases involving skin, aging, and blood sugar, as well as adult diseases. Conclusions : In this study, natural products patents registered in the Korean Intellectual Property Office were analyzed. The analyses results showed the kinds of natural products that had been employed for the treatment of certain diseases. However, natural products included in existing patents were minimal given that 4,174 species of indigenous plants are found in Korea. Thus, Korean institutes/companies should utilize unexplored plants to develop more value-added drugs.

Development of Natural Hazard Risk Map using Insured Claim Payouts and Its Application (보험 손실액을 활용한 자연재해 위험 지도 개발 및 적용방안 연구)

  • Kim, Ji-Myong;Park, Young Jun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2015.05a
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    • pp.257-258
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    • 2015
  • The amount of damages caused by natural hazards is consistently growing due to the unusual weather and extreme events. At the same time, property damage by natural hazards is rapidly increasing as well. Hence, we need systematic anti-disaster activities and consulting that can react to such a situation. To address these needs, we investigated and analyzed insured claim payouts from natural hazards by administrative area, and calculate the risk index utilizing GIS. According to the index, this map is identifying the areas of greatest natural hazard risk. The ranking of natural disaster vulnerability based on the risk index, and risk grades were divided into five based on the ranking. This map integrates the natural hazard losses to assist in comprehensive and effective loss prevention activities using analysis of regional loss claims from natural hazards. Moreover, this map can be as utilized as loss mitigation and prevention activities to verify the distribution of exposure and hazards.

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