통합 검색 | Korea Science

이지윤;장시훈;박수일
- 한국포장학회지
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- 제15권1호
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- pp.25-32
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- 2009
It is now widely recognized that the disposal of packaging waste is an increasing environmental concern. Recent interest in polymer waste management of packaging materials has added incentive to the research. Poly(vinyl alcohol) is a readily biodegradable water-soluble polymer. However, this polymer cannot be processed by conventional extrusion technologies because the melting point of PVA is close to its decomposition temperature. Therefore, PVA films have been mostly prepared by solvent casting from water. Applications of PVA include sizing, binders, fibers, and films for agricultural chemicals and hospital laundry bags. A better understanding of PVA films, which also play important roles in the degradation of plastics, will expand the usage of PVA. Composite films based on PVA generally exhibit better mechanical and thermal properties than pure PVA. The aim of this review article is to review types, formation, and properties of PVA films and PVA based composite films used in packaging related researches.
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이승재;이원기
- 한국환경과학회지
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- 제28권5호
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- pp.503-509
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- 2019
To prevent environmental pollution caused by leakage of leachate from waste landfill, vinyl acetate-ethylene (VAE) resin is applied to liner and cover materials to improve their performance. Styrene, styrene butadiene rubber, and VAE are widely used as polymer resins that have excellent water resistance and durability. Further, VAE resin is known to have additional advantages such as adhesion to nonpolar materials and resistance to saponification as a copolymer. In this study, the effect of VAE content on the properties of liner and cover materials was studied. The water and air content ratios, bending and compressive strengths, water absorption ratio, and coefficient of permeability of these materials were measured. The liner and cover materials with 4 wt% VAE showed good properties.
https://doi.org/10.5322/JESI.2019.28.5.503 인용 PDF KSCI

Bazrafkan, Aryan;Habibi, Alireza;Sayari, Arash
- Advances in concrete construction
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- 제10권6호
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- pp.463-478
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- 2020
Multiple mathematical modeling for prediction of slump, compressive strength and depth of water penetration at 28 days were performed using statistical analysis for the concrete containing waste limestone powder as partial replacement of sand obtained from experimental program reported in this research. To extract experimental data, 180 concrete cubic samples with 20 different mix designs were investigated. The twenty non-linear regression models were used to predict each of the concrete properties including slump, compressive strength and water depth penetration of concrete with waste limestone powder. Evaluation of the models using numerical methods showed that the majority of models give acceptable prediction with a high accuracy and trivial error rates. The 15-term regression models for predicting the slump, compressive strength and water depth were found to have the best agreement with the tested concrete specimens.
https://doi.org/10.12989/acc.2020.10.6.463 인용 KSCI

Perianez, Raul
- 방사성폐기물학회지
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- 제20권3호
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- pp.321-338
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- 2022
The transport of radionuclides at oceanic scales can be assessed using a Lagrangian model. In this review an application of such a model to the Atlantic, Indian and Pacific oceans is described. The transport model, which is fed with water currents provided by global ocean circulation models, includes advection by three-dimensional currents, turbulent mixing, radioactive decay and adsorption/release of radionuclides between water and bed sediments. Adsorption/release processes are described by means of a dynamic model based upon kinetic transfer coefficients. A stochastic method is used to solve turbulent mixing, decay and water/sediment interactions. The main results of these oceanic radionuclide transport studies are summarized in this paper. Particularly, the potential leakage of ¹³⁷Cs from dumped nuclear wastes in the north Atlantic region was studied. Furthermore, hypothetical accidents, similar in magnitude to the Fukushima accident, were simulated for nuclear power plants located around the Indian Ocean coastlines. Finally, the transport of radionuclides resulting from the release of stored water, which was used to cool reactors after the Fukushima accident, was analyzed in the Pacific Ocean.
https://doi.org/10.7733/jnfcwt.2022.029 인용 PDF KSCI

박남배;길대수;이헌모
- 환경위생공학
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- 제16권2호
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- pp.24-31
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- 2001
This study was aimed to evaluate biodegradability for various food waste using anaerobic batch digestion. In the anaerobic biodegradability study of each food waste according to occurrence source, the cumulative methane productions of water melon and melon were 375, and 354ml and that of cucumber, fresh cabbage, radish, sprouted bean were 366, 364, 374, 384, 355ml and that of noodle, boiled rice and fish were 432, 409 and 477ml $CH_{4/g}$ VS add, respectively. And methane yield rate was about 84.1~97.2%. The reaction rate coefficiency(k) was $0.00495~0.2022day^{-1}$.
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