• Advances in environmental research
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• v.3 no.4
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• pp.337-353
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• 2014

The determination of the effectiveness of the immobilization of blasting dust (waste generated in galvanic activities) in cement matrix, as well of mechanical, physical and microstructural properties of concrete paving blocks produced with partial replacement of cement was the objective of this work. The results showed that blasting dust has high percentage of silica in the composition and very fine particle size, characteristics that qualify it for replacement of cement in manufacturing concrete blocks. The replacement of Portland cement by up to 5% residues did not cause a significant loss in compressive strength nor increase in water absorption of the blocks. Chemical tests indicated that there is no problem of leaching or solubilization of contaminants to the environment during the useful life of the concrete blocks, since the solidification/stabilization process led to the immobilization of waste in the cement mass. Therefore, the use of blasting dust in the manufacture of concrete paving blocks is promising, thus being not only an alternative for proper disposal of such waste as well as a possibility of saving raw materials used in the construction industry.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.3
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• pp.410-420
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• 2012

The heavy reliance on fossil fuels, especially oil and gas has triggered the global energy crisis. Continued use of petroleum fuels is now widely recognized as unsustainable because of their depleting supplies and degradation to the environment. To become less dependent on fossil fuels, current world is shifting paradigm in energy by developing alternative energy sources mainly through the utilization of renewable energy sources. In particular, bioenergy recovery from wastes with the help of microorganism is viewed as one of the promising ways to mitigate the current global warming crisis as well as to supply global energy. It has been proved that microorganism can generate power by converting organic matter into electricity using microbial fuel cells (MFCs). MFC is a bioelectrochemical device that employs microbes to generate electricity from bio-convertible substrate such as wastewaters including municipal solid waste, industrial, agriculture wastes, and sewage. Sustainability, carbon neutral and generation of renewable energy are some of the major features of MFCs. However, the MFC technology is confronted with a number of issues and challenges such as low power production, high electrode material cost and so on. This paper reviews the recent developments in MFC technology with due consideration of electrode materials used in MFCs. In addition, application of biocathodes in MFCs has been discussed.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1400-1401
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• 2011

RPS(Renewable Portfolio Standard) recently with the introduction of a new solar power development as the market expands, land shortage of solar power as an alternative site for installing solar water development has emerged. Solar water dams, reservoirs and water by taking advantage of available solar power development a new concept of private forest land in a way does not involve destruction of the forest land and water resources through efficient use of environmentally friendly energy production and water quality improvement There are a variety of benefits. This paper won the nation's first solar power to enforce the selection of the optimal location for solar power's award for planning theory and research techniques are intended to establish. Award of the solar system through the analysis of a few research-related materials and renewable energy systems project implementation process to establish an initial investigation techniques as well as the existing dam located about fitness will be assessed. In this study, solar water conducting business in the current analysis with considerable planning and installation of solar installation for the economic and environmental cost of the evaluation period and is expected to be able to give you one.

• Journal of the Korean Electrochemical Society
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• v.15 no.3
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• pp.135-148
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• 2012

Ionic liquids are steadily attracting interests throughout a recent decade and their application is expanding into various fields including electrochemistry due to their unique properties such as non-volatility, inflammability, low toxicity, good ionic conductivity, wide electrochemical potential window and so on. These features make ionic liquids become an alternative solution for electrodeposition of metals that cannot be electroplated in aqueous electrolytes. In this review, we classify investigated metals into three categories, which are light (Li, Mg), refractory (Ti, Ta) and noble (Pd, Pt, Au) metals, rather than covering the exhaustive list of metals and try to update the recent development in this area. In electrodeposition of light metals, granular fine Li particles were successfully obtained while the passivation of electrodeposited Mg layers is an obstacle to reversible deposition-dissolution process of Mg. In the case of refractory metals, the quality of Ta and Ti deposit particles was effectively improved with addition of LiF and pyrrole, respectively. In noble metal category, EMIM TFSA ionic liquid as an electrolyte for Au electrodeposition was proven to be effective and BMP TFSA ionic liquid developed a smooth Pd deposit. Pt nanoparticle production from ionic liquid droplet in aqueous solution can be cost-effective and display an excellent electrocatalytic activity.

• Journal of Hydrogen and New Energy
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• v.16 no.2
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• pp.159-169
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• 2005

Cellulose, consisted of 45 wt% in wood, is usable as fuels and heavy oil additives if depolymerized to monomer unit, because the chemical structures are similar to high octane materials found in gasoline. In this study, thermochemical degradation by solvolysis reaction of cellulose such as the effect of reaction temperature, reaction time and type of solvent on conversion yield and degradation products were investigated. It was found that the effectiveness of the solvent on the sovolysis reaction was as follows; acetone>n-butanol>tetralin. When acetone was used as a solvent, the highest cellulose conversion was observed to be 91.8% at 500$^{\circ}C$, 40min. Combustion heating value of liquid products from thermochemical conversion processes was in the range of 7,330${\sim}$7,410cal/g. The energy yield and mass yield in acetone-solvolysis of cellulose was as high as 66.8% and 37.0 g oil/100g raw material after 40min of reaction at 400$^{\circ}C$. Various aliphatic and aromatic compounds were detected in the cellulose solvolysis products. The major components of the solvolysis products, that could be used as fuel, were mesityl oxide, mesitylene, isophorone.

• Resources Recycling
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• v.13 no.1
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• pp.3-13
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• 2004

The use of biomass has attracted extensive attention from the beginning of civilization. However, intensive researches on the biomass from the view point of the development of alternative energy have been carried out just recently. Fast pyrolysis, as a tool for the utilization of the biomass as the secondary energy source has drawn great attentions due to high applicability for the production of several valuable materials from biomass. This review paper focuses on the recent developments of pyrolysis process and reports the characteristics of bio-oil, which is the main product of fast pyrolysis of biomass.

• Journal of Hydrogen and New Energy
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• v.18 no.1
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• pp.85-94
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• 2007

Rice straw, produced as an agricultural by-product, is usable biomass as fuels if depolymerized to monomer unit, because the chemical structure are similar to high octane materials found in gasoline. In this study, parameters of thermochemical degradation by solvolysis reaction of rice straw such as the effect of reaction temperature, reaction time and type of solvent on conversion yield and degradation products were investigated. It was found that the effectiveness of the solvent on the solvolysis reaction was as follows; acetone>cresol>butanol. When acetone was used as a solvent, the highest rice straw conversion was observed to be 91.5% at $500^{\circ}C$, 40 min. Combustion heating value of liquid products from thermochemical conversion processes was in the range of 7,380 cal/g. The energy yield and mass yield in acetone-solvolysis of rice straw was as high as 69.0% and 38.2 g-oil/100g-raw material after 40 min of reaction at $350^{\circ}C$. Various aliphatic and aromatic compounds were detected in the rice straw solvolysis products. The major components of the solvolysis products, that could be used as fuel, were 4-methyl-2-pentanone, 3,5,5-trimethyl-2-cyclopentan-1-one as ketones.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.291-291
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• 2010

Organic solar cells have attracted much interest due to the potential advantage of the lightness, simple solution processing and flexibility. Until recently, the focus of organic solar cells research has been on optimization of material processing to improve the power conversion efficiency. However, area scaling is an important position for alternative to the market dominating solar cells. Spray deposition technologies have advantage of less material wastage and possibility of large scale photoactive area coating when compared with spin coating process. We investigated the performance of organic solar cells as a function of active area using two types of deposition process. The commonly used process is spin coating which can be fabricated organic materials deposition for devices. Spray deposition process compare with spin coating for large-area organic solar cells. The spray deposition organic layer shows excellent performance up to the active area of $4\;cm^2$ with the PCE of ~3.0 % under AM.1.5 simulated illumination with an intensity of $100mW/cm^2$. This indicates that the spray deposition process can be used as a mass production process for evaluating large-area organic solar cells.

• Korean Journal of Environmental Agriculture
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• v.27 no.3
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• pp.285-291
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• 2008

A global binding agreement was adopted with the leading of United Nations Environment Program (UNEP) on May 22, 2001 in Stockholm to regulate the production and distribution on persistent organic pollutants (POPs). The agreement took effectuation with the ratification of 59 countries from the approval of 151 countries on May 17, 2004. After the approval on October 4, 2001, South Korea performed systematical investigation on POP-related substances such as chlordane, dichloro diphenyl trichloroethane (DDT), hexachlorobenzenes (HCB), heptachlor, polychlorinated biphenyls (PCBs) to get ready for the ratification of the convention with country-specific exemption. The domestic distributions of those chemical substances have been officially prohibited since the late 1960s to the early 1980s. Although there were occasional reports for the detection of some of those chemical substances, those performed minute signification in their existence in the environment. A series of investigation with documentary examination and fact-finding survey showed the possibility for the ratification on the convention without country-specific exemption.

• Microbiology and Biotechnology Letters
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• v.48 no.3
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• pp.366-372
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• 2020

Since, side effects of antibiotics are frequently emphasized these days, their use is gradually diminishing, and alternative drugs are being developed. We have sought to reintroduce them as raw materials for human health as conventional 'weapons' that have been retired after their historical duties. In this study, we investigated the anti-inflammatory effects of lincomycin (LIN), on lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Our findings show that LIN potently inhibited production of LPS-induced proinflammatory mediators, such as nitric oxide (NO) and prostaglandin E₂ (PGE₂), without cytotoxicity. Consistent with these findings, LIN strongly decreased protein expression levels of inducible NO synthase (iNOS) and cyclooxygenase (COX-2). Furthermore, LIN reduced pro-inflammatory cytokines such as tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β. To further elucidate the mechanisms of these inhibitory effects of LIN, we studied LPS-induced IκB-α degradation, and mitogen-activated protein kinase (MAPK) phosphorylation. LIN suppressed downregulation of inhibitory κB (IκB-α) degradation, and the phosphorylation of the c-Jun N-terminal kinase (JNK) pathway. Based on these results, we suggest that LIN may be considered a potential candidate as an anti-inflammatory cosmetic or a medicine for human health.