• Title/Summary/Keyword: water-friendly

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Preparation and Coating of Red Colored Artificial Pearl by CVD Method (CVD법을 이용한 적색 인조진주 코팅 및 제조)

  • Shin, Cheol-Woo;Choi, Kyoung-Rim;Lee, Dong-Kyu
    • Journal of the Korean Applied Science and Technology
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    • v.35 no.3
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    • pp.857-864
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    • 2018
  • Demand for developing artificial green pearl that meets the needs of modern people has been increasing. In this paper, eco-friendly inorganic pearlescent pigment was used instead of organic pigment and urethane resin was substituted for nitrocellulose which has been used as main materials in previous preparation method, increasing gloss from 73.4% to 86.7%. Urethane was coated on substrate before finishing with CVD, resulting high gloss of 96%. Colorimeteric analysis shows that a* and b* of CIE value was changed from +37.7 and +24.5 to +31.9 and +14.2 respectively because of CVD finishing, obtaining colorful, high gloss and durable artificial pearl. Quality and toxicity of samples was established by chemical resistance, glossiness, colorimeter, surface roughness, wear resistance, content of heavy-metal, and salt water test.

Mechanical Properties on Resin of New Austrian Tunneling Coatings on Stainless Steel 316L (스테인레스강 316L 상의 New Austrian Tunneling Method Coatings의 수지에 관한 기계적 특성)

  • Lee, Jooyoub;Sung, Wanmo;Kim, Joohan;Seong, Minjeong;Kim, Ki-Jun
    • Journal of the Korean Applied Science and Technology
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    • v.37 no.4
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    • pp.1034-1040
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    • 2020
  • The mechanical properties of NATM resin of synthetic polyurethane-epoxy resin for stainless steel were measured by SEM, FT-IR, tensile properties, and specific mass loss by EIS analysis, etc. As interest in eco-friendly medium coatings increased, the Heavy duty coatings were synthesized for various metals such as stainless steel composed of Polyol, MDI, water bored Epoxy resin, filling agent, silicon surfactant, catalyst etc. The coatings of synthetic NATM resin were increased tensile strength due to various temperature change, and the low-Specific Mass Loss was measured in a highly electrolytic solution. In conclusion, the NATM coatings composed of polyurethane and waterbored Epoxy, polyurea resin were synthetic microstructure with cross linkage can be good material for coating of anticorrosion of metal substrates such as stainless steel.

A high-effective method to separate nicotine from the tobacco-specific carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) mixtures using electrodialysis

  • Ge, Shaolin;Li, Wei;Zhang, Zhao;Li, Chuanrun;Wang, Yaoming
    • Membrane and Water Treatment
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    • v.8 no.3
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    • pp.245-257
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    • 2017
  • The separation of nicotine and tobacco-specific N-nitrosamines is a tough problem in tobacco industry. In this study, separation of nicotine from 4-(methylnitrosamino) -1-(3-pyridyl)-1-butanone (NNK) mixtures was investigated using electrodialysis by taking the principle of the protonation status difference between these two components. The results indicated that the solution pH has a dominant impact on the separation process. In a pH range of 5-7, nicotine molecules are existed as mono- and di-protonated ions and can be separated from the uncharged NNK molecules. The acidic electrolyte is conducive to the separation process from the point of flux and energy consumption; while the alkaline electrolyte has negative impact on the separation process. A current density of $10mA/cm^2$ is an appropriate value for the separation process. The lowest energy consumption of the separation process is 0.58 kWh/kg nicotine with the process cost to be estimated at only $0.208 /kg nicotine. Naturally, electrodialysis is a high-efficiency, cost-effective, and environmentally friendly process to separate and purify nicotine from tobacco juice.

A Study on Properties of Polyurethane-Epoxy Hybrid Coatings on Stainless Steel 316L at Various Temperatures (스테인레스강 316L의 다양한 온도에서 폴리우레탄-에폭시 복합코팅 특성에 관한 연구)

  • Sung, Wanmo;Kim, Kijun;Kim, Joohan;Seong, Minjeong
    • Journal of the Korean Applied Science and Technology
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    • v.36 no.4
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    • pp.1358-1364
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    • 2019
  • The mechanical properties of Heavy duty resin of synthetic polyurethane-epoxy resin for stainless steel were measured by SEM, FT-IR, tensile properties, and specific mass loss by EIS analysis, etc. As interest in eco-friendly medium coatings increased, the Heavy duty coatings were synthesized for various metals such as stainless steel composed of Polyol, MDI, water bored Epoxy resin, filling agent, silicon surfactant, catalyst etc. The coatings of synthetic Heavy duty resin were increased tensile strength due to various temperature change, and the low-Specific Mass Loss was measured in a highly electrolytic solution. In conclusion, the Heavy Duty coatings composed of polyurethane and waterbored Epoxy resin were synthetic microstructure with cross linkage can be good material for coating of anticorrosion of metal substrates such as stainless steel.

Present Status and Future Vision of EIA for Railroad Construction Projects (철도건설사업 환경영향평가의 현황과 과제)

  • Lee Hyun-Woo;Lee Young-Joon;Park Young Min;Yoon Mikyung
    • Proceedings of the KSR Conference
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    • 2004.06a
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    • pp.296-302
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    • 2004
  • After the Rio declaration on environment and development in 1992, developed countries are undertaking 'environmentally sustainable transportation (EST)' projects. To meet the needs for EST, current transportation policies in Korea are rapidly reforming and one of its concerns is modernizing and upgrading railway freight system. Planning new railroad construction projects is increasing and subsequent environmental impact assessment (EIA) demands improvements, especially in both the EIA and decision making systems. In this paper, we discuss the present status of EIA for railroad construction projects, especially, by analyzing the EIA documents accumulated for last six years. The EIA for railroad construction projects .accounts for only $4.9\%$ of total project EIAs during 1998-2003. However, the portion is gradually increasing. Major environmental concerns for EIA in railroad construction projects were geomorphological and ecological changes, protection of rare organisms, air pollution, water quality, wast management, noise, etc. We also compared the characteristics of environmental impacts of railroad construction with those of vehicle road construction. The result shows that railroad construction usually requires 3${\~}$4 times longer tunnels and bridges for a given length than vehicle road construction. In addition, the amounts of geomorphological and ecological changes (road-cutting, embankment, devegetation, etc.) in railroad construction were generally less than $40\%$ of those in vehicle road construction. In order to develop environmentally friendly railway systems, monitoring studies for environmental impacts of railroads such as habitat fragmentation and road kills, dispersal of alien plants, tunnelling effects on groundwater and vegetation, and noise impacts are highly required.

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Experimental Study on Heating Performance Characteristic of 100 kW Heat Pump to Generate ℃ Steam (120℃ 스팀 생성을 위한 100 kW급 히트펌프의 실험적 연구)

  • Wang, Eunseok;Na, Sun-Ik;Lee, Gilbong;Baik, Young-Jin;Lee, Young-Soo;Lee, Beomjoon
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.30 no.2
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    • pp.100-106
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    • 2018
  • Recently, the development of a heat pump technology to recover process waste heat and to generate steam of $120^{\circ}C$ or higher required for industrial processes, has attracted attention. The research of conventional heat pump utilizing the available energy is used primarily for air conditioning, and the production temperature is about $60^{\circ}C$, so it is difficult to utilize it for industrial use. Therefore, in this study, we developed a steam heat pump (SGHP) which recovers the waste heat of process and generates steam at $120^{\circ}C$. The low-pressure refrigerant R245fa, considered to be an eco-friendly refrigerant, has been selected as the refrigerant for SGHP in this study since its Ozone Depletion Potential (ODP) is zero and the Global Warming Potential (GWP) is relatively low. A flash tank functioning as a phase separator was installed in the rear stage of the condenser, and the saturated water of high temperature was decompressed to generate steam. It was started at the initial temperature of $70^{\circ}C$, and it was confirmed that $120^{\circ}C$ steam was produced after the system stabilized. We have conducted experiments by modifying the system, and ultimately achieved a heating capacity of 101.4 kW and a COP of 3.05.

A Study on the Development and Educational Effect of the Environmental Management Integrated Leader Program (환경경영 통합 리더 프로그램의 개발과 효과에 관한 연구)

  • 정연돈
    • Hwankyungkyoyuk
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    • v.10 no.2
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    • pp.249-268
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    • 1997
  • This Study developed 'Environment Management Integrated Leader(EMIL)' program and evaluated the effect of the Program. The procedure of EMIL program development is as follows; 1) Identifying the training needs Through the interview and discussion with corporate environmental staff and research members, training need are collected. 2) Setting the training objectives 30 objectives are developed through specifying and organizing the training needs. 3) Determining the scopes of the program This program consists of the four scopes. First, the scope of Environmentally Acceptable Management is developed based on ISO 14000 and certification of environmentally friendly business. Second, the scope of Environmentally Acceptable Technology includes air pollution, water pollution, solid wasted management, and pollution prevention. Third, the scope of Integrated Environmental Management focuses on master plan, green marketing, green production, and green accounting. Finally, the scope of Integrated Environmental Concepts focuses on food pollution, environmental activities, and bio-diversity. 4) Selecting the training methods Various methods are used such as off-site visits, exercises, case study, workshop, discussion, role-playing as well as lecture. 5) Implementing the program 49 trainees participated the program for 6weeks. All trainees are working for D. Company Group. 6) Measuring training effects To evaluate the effects of the program, pre-post training evaluation method is used. The results are highly significant at all 4 scopes by the p<.01. This study has some implications in order to establish the environmental management climate. First, the development of new environmental education program for management is necessary. Second, Vast investment are required. Third, more systematic approaches are desired in environmental education. Lastly, more customized program development and implementation to fit in industries will accelerate the expansion of environmental concept.

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Physical and Chemical Properties of Kapok (Ceiba pentandra) and Balsa (Ochroma pyramidale) Fibers

  • Purnawati, Renny;Febrianto, Fauzi;Wistara, I Nyoman J;Nikmatin, Siti;Hidayat, Wahyu;Lee, Seung Hwan;Kim, Nam Hun
    • Journal of the Korean Wood Science and Technology
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    • v.46 no.4
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    • pp.393-401
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    • 2018
  • Natural fibers derived from lignocellulosic materials are considered to be more environment-friendly than petroleum-based synthetic fibers. Several natural fibers, such as seedpod fibers, have a potential for development, including kapok and balsa fibers. The characteristics of both fibers were evaluated to determine their suitability for specific valuable applications. The purpose of this study was to analyze some important fundamental properties of kapok and balsa fibers, including their dimensions, morphology, chemical components, and wettability. The results showed that the average fiber lengths for kapok and balsa were 1.63 and 1.30 cm, respectively. Kapok and balsa fibers had thin cell walls and large lumens filled with air. The kapok fiber was composed of 38.09% ${\alpha}-cellulose$, 14.09% lignin, and 2.34% wax content, whereas the balsa fiber was composed 44.62% ${\alpha}-cellulose$, 16.60% lignin, and 2.29% wax content. The characteristics of kapok and balsa fibers were examined by X-ray diffraction, Fourier-transform infrared spectroscopy and differential scanning calorimetry analyses. The contact angle of the distilled water on kapok and balsa fibers was more than $90^{\circ}$, indicating that both fibers are hydrophobic with low wettability properties because of to the presence of wax on the fiber surface.

Modified Drum Priming and Exogenous Application of 24-Epibrassinolide (24-EBL) for Enhancing Germination under High Temperature Condition in Lettuce Seeds

  • Kang, Won Sik;Kim, Min Geun;Kim, Du Hyun
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2018.10a
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    • pp.86-86
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    • 2018
  • This study was conducted to investigate the effects of modified drum priming and 24-Epibrassinolide (24-EBL) treatment to improve the seed quality for export. 40, 50 and 60% seed moisture content (SMC) of hydrated seeds were incubated for 16 and 24 h in a container with a relative humidity of 99% at 26 rpm for a modified drum priming treatment. The treated seeds were sown at $20^{\circ}C$ and $30^{\circ}C$ (12/12h, light/dark) with four replications of 25 seeds on pleated paper. The seeds were hydrated with water or 24-EBL solutions of $10^{-7}$, $10^{-8}$ and $10^{-9}M$, respectively. The germination of the modified drum primed seeds (24 h incubation after 60% SMC hydration) improved to 1.6 days mean germination time (MGT) and $46%{\cdot}day^{-1}$ germination rate (GR), while the untreated seeds showed 2.1 days MGT and $28%{\cdot}day^{-1}$ GR. The modified drum priming (60% SMC and 24 h incubation with $10^{-9}M$ 24-EBL) showed improved results in MGT (1.8 days) and GR (55%) at $20^{\circ}C$, whereas untreated seeds showed 2.3 days MGT and 44% GR. Under $30^{\circ}C$, germination of modified drum primed seeds was significantly improved in GP (80%), GR ($31%{\cdot}day^{-1}$), HS (55%) and MGT (3.3 days), however, untreated seeds showed decreased GP (27%), GR ($22%{\cdot}day^{-1}$), HS (55%) and MGT (4.8 days). This study showed that the germination of lettuce seeds is enhanced by 24 h drum incubation with 24-EBL and this method can be used effectively to achieve the benefits of early germination and uniform seedling development. In addition, these treatments circumvent thermo-dormancy of lettuce seed and have a possibility of high-quality and environment-friendly seed processing.

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A Study on the Stability Analysis of the Bank Revetment at Urban Streams in Flood Times (홍수시 도시하천의 호안 안정성 분석에 관한 연구)

  • Kim, Chul;Park, Nam-Hee
    • Journal of the Korean Society of Hazard Mitigation
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    • v.10 no.6
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    • pp.139-145
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    • 2010
  • Recently, close-to-nature stream improvement works have been carried out in urban streams, where eco-friendly bank revetment methods have been adopted. These bank revetment methods are vulnerable to be damaged or washed away by floods compared to the traditional methods which use concrete materials. Damage analysis methods on the urban streams by the floods of severe rain storm are presented. The analysis methods are the graph-using method and the grid method, which are derived from the survey results at Gwangju stream. Damage analysis grid which is intersected velocity grid and material strength grid is the highest correlation with the damage survey grid. The biggest damage on the bank revetments have been occurred around the crossing structures. Big damages have also been occurred in the connection of low water revetment and the terrace land, and around the structures in the terrace land of the stream.