• Title/Summary/Keyword: green materials

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Content Analyses of Green Life-Educational Materials in Korean and Japanese Middle School Horne Economics Textbooks (한.일 중학교 가정교과서의 녹색생활교육 내용분석)

  • Park, Mi-Jeong;Cho, Jae-Soon;Jang, Sang-Ock;Lee, Yon-Suk
    • Journal of Korean Home Economics Education Association
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    • v.23 no.1
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    • pp.1-17
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    • 2011
  • The purpose of this paper was to explore the materials in the Korean and Japanese Home Economics textbooks in middle school with the perspective of green life education. Home Economics is one of the relevant subjects to green growth education. Therefore, home economics teachers need to teach green life based on the low $CO_2$-green growth in the class. Sustainable living at home has been emphasized as one of the main importance of Home Economics since the first curriculum period. However, it is required to reinforce in the 2009 revised curriculum. The content analyses had been done to explore the materials of five areas in the 8 Korean and 2 Japanese junior highschool Home Economics textbooks through two checking steps. Each subject area of Home Economics had various form of materials such as terminology, table figure pictures, reading, and activity, related to green life related to environmental, economic, and social sustenance. The forms and the quantity of materials were some what differ by subject areas as well as textbooks. The levels of material contents were ranged from the knowledge, recognition, to intention to practicum of green life. The green life materials were more likely practical in Japanese textbooks rather than Korean ones. It is recommended teachers to choose the valuable materials over the textbooks and practical green life should clearly mentioned in home economics curriculum to be showed in textbooks.

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Density Functional Theory Study on Triphenylamine-based Dye Sensitizers Containing Different Donor Moieties

  • Xu, Jie;Wang, Lei;Liang, Guijie;Bai, Zikui;Wang, Luoxin;Xu, Weilin;Shen, Xiaolin
    • Bulletin of the Korean Chemical Society
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    • v.31 no.9
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    • pp.2531-2536
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    • 2010
  • Density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations have been employed to investigate the molecular structures and absorption spectra of two dyes containing diphenylaniline and 4-diphenylamino-diphenylaniline as donor moiety (TPA1 and TPA3). The geometries indicate that the strong conjugation is formed in the dyes. The electronic structures suggest that the intramolecular charge transfer from the donor to the acceptor occurs, and the electron-donating capability of 4-diphenylamino-diphenylaniline is stronger than that of diphenylaniline. The computed highest occupied molecular orbital (HOMO) energy levels are -5.31 and -4.90 eV, while the lowest unoccupied molecular orbital (LUMO) energies are -2.29 and -2.26 eV for TPA1 and TPA3, respectively, revealing that the interfacial charge transfer between the dyes and the semiconductor electrode are electron injection processes from the photon-excited dyes to the semiconductor conduction band. Furthermore, all the experimental absorption bands of TPA1 and TPA3 have been assigned according to the TDDFT calculations.

Low-Temperature Sintering Behavior of Aluminum Nitride Ceramics with Added Copper Oxide or Copper

  • Hwang, Jin-Geun;Oh, Kyung-Sik;Chung, Tai-Joo;Kim, Tae-Heui;Paek, Yeong-Kyeun
    • Journal of the Korean Ceramic Society
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    • v.56 no.1
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    • pp.104-110
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    • 2019
  • The low-temperature sintering behavior of AlN was investigated through a conventional method. $CaF_2$, CuO and Cu were selected as additives based on their low melting points. When sintered at $1600^{\circ}C$ for 8 h in $N_2$ atmosphere, a sample density > 98% was obtained. The X-ray data indicated that eutectic reactions below $1200^{\circ}C$ were found. Therefore, the current systems have lower liquid formation temperatures than other systems. The liquid phase showed high dihedral angles at triple grain junctions, indicating that the liquid had poor wettability on the grain surfaces. Eventually, the liquid was likely to vaporize due to the unfavorable wetting condition. As a result, a microstructure with clean grain boundaries was obtained, resulting in higher contiguity between grains. From EDS analysis, oxygen impurity seems to be well removed in AlN lattice. Therefore, it is believed that the current systems are beneficial for reducing sintering temperature and improving oxygen removal.

Influence of Coating Process on Properties of BTA (Benzotriazole) Coating Film for Outdoor Bronze Artifacts Conservation (옥외 청동문화재 보존을 위한 BTA 방청 피막의 특성에 미치는 코팅 조건의 영향)

  • Shim, G.T.;Yoo, Y.R.;Kwon, Y.H.;Kim, Y.S.
    • Korean Journal of Metals and Materials
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    • v.47 no.10
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    • pp.652-659
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    • 2009
  • Many ancient and historical artifacts were made by copper and its alloys. In the case of outdoor exposure artifacts, the surface could be suffered from corrosion and tarnish by the reaction with its environment. In order to preserve the artifacts, surface treatment would be needed and BTA coating has been usually applied to tin-bronze. This paper dealt with the evaluation of the properties of BTA coated film using a linear polarization method and AC impedance measurement. On the base of corrosion rate and film resistance for the specimen formed by coating process, optimum coating conditions are as follows; 3 cycles brushing or 3 cycles spraying coatings for natural dried process and 1 cycle brushing coating or 5 cycles spraying coating for hot-air dried process.

VUV luminescence properties of a novel green-emitting $(Y,Gd)Ga_3(BO_3)_4$:Tb phosphor

  • Moon, Young-Min;Choi, Sung-Ho;Lim, Sang-Ho;Jung, Ha-Kyun
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08b
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    • pp.1561-1564
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    • 2007
  • $Tb^{3+}-activated$ green-emitting $(Y,Gd)Ga_3(BO_3)_4$ phosphor has been investigated. The main absorption was in the $120{\sim}238$ nm and exhibited a green emission with the 545 nm and several peaks due to inner shell transition of $Tb^{3+}$ ion. With the optimized $Tb^{3+}$ concentrations, the maximum emission brightness was 90% of the $Zn_2SiO_4$:Mn phosphor.

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The Necessity Analysis of Development Waterproofing Materials and Methods of Construction Technologies for Green Roof (옥상녹화를 위한 방수재료 및 공법개발의 필요성에 관한 분석)

  • Kwon, Shi-Won;Oh, Mi-Hyun;Kang, Hyo-Jin;Oh, Sang-Keun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2003.11a
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    • pp.107-111
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    • 2003
  • The need for this study must be considerable, as being activate of green roofs research that the organization and construction obtain access to more development technologies. Nevertheless, the green roofs system has begun to apply since 1980's, the green roofs technology was restricted to develop without verification of technologies such as a load or water leakage. There is a limit as urethane waterproofing to almost domestic waterproofing materials and methods of construction for general green roofs. The introduction of materials and methods of construction which are appropriated to property of green roofs could be a decisive factor in a long-range durability and economical maintenance cost, moreover, it support to variety construction system and organization. This present paper describes a necessity of waterproofing and root barrier system is one of the sub-organization based on green roofs construction, which have enormously large impact on the durability.

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The Necessity Analysis of Development Waterproofing Materials and Methods of Construction Technologies for Green Roofs (옥상녹화시스템의 방수재료 및 공법개발에 관한 필요성 분석)

  • Kwon, Shi-Won;Jo, Il-Gyu;Bae, Kee-Sun;Oh, Sang-Keun
    • Journal of the Korea Institute of Building Construction
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    • v.4 no.1
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    • pp.111-118
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    • 2004
  • The need for this study must be considerable. as being activate of green roofs research that the organization and construction obtain access to more development technologies. Nevertheless, the green roofs system has begun to apply since 1980's, the green roofs technology was restricted to develop without verification of technologies such as a load or water leakage. There is a limit as urethane waterproofing to almost domestic waterproofing materials and methods of construction for general green roofs. The introduction of materials and methods of construction which are appropriated to property of green roofs could be a decisive factor in a long-range durability and economical maintenance cost, moreover, it support to variety construction system and organization. This present paper describes a necessity of waterproofing and root barrier system is one of the sub-organization based on green roofs construction. which have enormously large impact on the durability.

A Study of R&D Paradigm For the Materials Technologies Involving Environmental Consciousness (재료기술의 환경패러다임 모색)

  • 하재우;권식철;김성준
    • Journal of Korea Technology Innovation Society
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    • v.2 no.1
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    • pp.104-117
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    • 1999
  • The R&D paradigm for the Materials Technologies involving Environmental Consciousness(MTEC) is sought in this paper with an emphasis on the background and importance of the METC. In this paper the MTEC is defined as "Green Materials Technology", and the Green Materials Technology is classified into four categories based on life cycle of the materials; \circled1Ecomaterials technology(materials design), \circled2Envimatec technology (manufacturing process), \circled3Materials life technology (use & maintenance) and \circled4Materials recycling technology (waste disposal). Each these four categories was introduced. In conclusion, the main R&D field and strategies for the four categories of the Green Materials Technology were suggested.

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Heat transfer of green timber wall panels (그린팀버월 패널의 열전달 특성)

  • Kim, Yun-Hui;Jang, Sang-Sik;Shin, Il-Joong
    • Korean Journal of Agricultural Science
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    • v.38 no.1
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    • pp.115-120
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    • 2011
  • 20% of total energy use to sustain temperature of building inside. In this reasons, researchers effort to improve the thermal insulation capacity with new wall system. Using appropriate materials and consisting new wall system should considered in energy saving design. OSB(Oriented strand board), Larch lining board used to consist wall system. $2{\sim}6$ Larch lining board has tongue & groove shape for preventing moisture. Comparing with gypsum board and green timber lining board as interior sheathing material, temperature difference of Green timber wall system was bigger than temperature difference of gypsum board wall system. This aspects indicate that Green timber wall system was revealed higher thermal insulation property than gypsum board wall system. Gypsum board portion transfer heat easily because temperature difference gradient of gypsum board wall system was smaller than OSB wall system. Total temperature variation shape of G-4-S and G-6-S show similar model but, temperature variation shape in green timber wall portion assume a new aspect. The purpose of this study was that possibility of thermal insulation variation and new composition of wall system identify to improve thermal insulation performance. In the temperature case, this study shows possibility of improving thermal insulation performance. Humidity, sunshine and wind etc. should considered to determine building adiabatic properties.