• Advances in nano research
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• v.10 no.2
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• pp.191-210
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• 2021

To compare the antifungal effect of two nanomaterials (NMs), nanoparticles of zinc oxide were synthesized by a chemical route and zinc oxide-based nanobiohybrids were obtained using green synthesis in an extract of garlic (Allium sativum). The techniques of X-Ray Diffraction (XRD), Infrared (IR) and Ultraviolet Visible (UV-Vis) absorption spectroscopies and Scanning (SEM) and Transmission Electron Microscopies (TEM) were used to determine the characteristics of the nanomaterials synthesized. The results showed that the samples obtained were of nanometric size (< 100 nm). To compare their antifungal capacity, their effect on Cercospora sp. was evaluated. Test results showed that both nanomaterials had an antifungal capacity. The nanobiohybrids (green route) gave an inhibition of fungal growth of ~72.4% while with the ZnO-NPs (chemical route), inhibition was ~87.1%. Microstructural studies using High Resolution Optical Microscopy (HROM) and ultra-structural analysis using TEM carried out on the treated strains demonstrated the effect of the nanofungicides on the vegetative and reproductive structures, as well as on their cell wall. To account for the antifungal effect presented by ZnO-NPs and ZnO nanobiohybrids on the fungi tested, effects reported in the literature related to the action of nanomaterials on biological entities were considered. Specifically, we discuss the electrical interaction of the ZnO-NPs with the cell membrane and the biomolecules (proteins) present in the fungi, taking into account the n-type nature of the ZnO semiconductor and the electrical behavior of the fungal cell membrane and that of the proteins that make up the protein crown.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3451-3453
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• 2010

• Journal of the Speleological Society of Korea
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• no.85
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• pp.21-24
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• 2008

The chlorophyta and thebryophyta are became extinct by the shutting out the light and low temperature in caves. Whenever they get the conditions, they grow again immediately. It is necessary to keep the illumination distance over 2m and use the indirect light. The effect of lamp light and temperature is very important in the control of green contamination but the water and moisture in caves are essential factors in green contamination in the show caves. It's better to get rid of green alae and mosses at early stage for the control of the increase of green contamination. They must be isolated completely without the dispersion with moist pieces of cloth or sponge. It is necessary to shut out the cave route periodically for the restoration of cave environments and ecosystem. It's better to use the lamp keeping illumination and restricting the ascension of heat for the control of green contamination.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1388-1390
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• 2013

Macroporous $SnO_2$ foam was successfully synthesized via a simple soft-chemical route by hybridization between alkylamine and tin(IV) oxide. According to X-ray diffraction (XRD) analysis, the as-prepared $SnO_2$ foam had a highly ordered lamella structure along the crystallographic c-axis, which transformed to a rutile phase after thermal treatment at $300^{\circ}C$. X-ray absorption spectroscopy (XAS) at the Sn K-edge revealed that $SnO_2$ particles in the hybrid material maintained their nanosized structure after hybridization with alkylamine. Scanning electron microscope (SEM) images clearly showed that the as-prepared $SnO_2$ foam had a macroporous structure. This synthetic route can be extended to the development of open frameworks with good electrochemical properties in battery applications.

• Journal of Electrochemical Science and Technology
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• v.2 no.3
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• pp.157-162
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• 2011

We report a simple route for synthesizing multi-dimensional structured silicon anode materials from commercially available bulk silicon powders via metal-assisted chemical etching process. In the first step, silver catalyst was deposited onto the surface of bulk silicon via a galvanic displacement reaction. Next, the silver-decorated silicon particles were chemically etched in a mixture of hydrofluoric acid and hydrogen peroxide to make multi-dimensional silicon consisting of one-dimensional silicon nanowires and micro-scale silicon cores. As-synthesized silicon particles were coated with a carbon via thermal decomposition of acetylene gas. The carbon-coated multi-dimensional silicon anodes exhibited excellent electrochemical properties, including a high specific capacity (1800 mAh/g), a stable cycling retention (cycling retention of 89% after 20 cycles), and a high rate capability (71% at 3 C rate, compared to 0.1 C rate). This process is a simple and mass-productive (yield of 40-50%), thus opens up an effective route to make a high-performance silicon anode materials for lithiumion batteries.

• Journal of the Korean Society for Marine Environment & Energy
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• v.5 no.1
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• pp.19-29
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• 2002

In this paper, the selection of transport route for import-export container cargo based on the sacrifice model and CO₂ emission was investigated. At first, the transportation of import-export container cargo, the transport share of each transport route, the CO₂ gas emission, the sacrifice model and the time value of import-export container cargo were investigated. And next, the selection of transport route based on the sacrifice model was investigated for the transport of import-export container cargo from Seoul to Pusan Port. Finally, the transport route was also selected by using the sacrifice model including the effect of CO₂ emission. The research results show that the transport route selection results of import-export container cargo based on the sacrifice model represents the present status of the transportation of import-export container cargo very well. And also the research results show that the reduction of transport time was very effective to increase the share of coastal transportation.

• Applied Chemistry for Engineering
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• v.21 no.6
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• pp.694-696
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• 2010

We have synthesized boron (or phosphorous) doped silicon nanoparticles (Si-NPs) by a solution process. The surfaces of the Si-NPs were terminated with various alkyl groups to form a protecting layer. The Si-NPs were characterized by UV-Vis, PL, FTIR, and NMR. Through a microwave sintering process, the crystalline thin films of the Si-NPs were prepared by removing the surface alkyl groups. The TEM and SEM images reveal that contiguous films as large as $200{\mu}m$ in diameter were formed with a cubic structure. The electrical conductivity of the Si film was controlled by a doping type.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.496-504
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• 2011

The region trunk line railroad route undergoes an influence on a large scale in train operation systematic reorganization. This keynote of the train operation not being to the consumer and not to be is because being to the supplier. The trunk line route user of region supply change of the supplier sensitively, accepts but, the demand unit will be able to change the supply massive demanders does not become and like that to accept this back is not the railroad the mean of transportation which grudge is different a mean of transportation mainly makes use. This hits to neither the gist of GLORY promotions of the railroad public corporation which pursues the railroad use which is ordinary even in the basis of governmental policy of stock of coal small green growth and not to be is arranged. For the railroad use activation of the region trunk line route consequently and to excavate the demand hindrance element and a demand lure element the inside and the outside defines and to observe the fluctuation of use importing in existing train operation systematic fluctuation, with the user tries analyzes the instance of the overseas railroad enterprise about the process which reflects the opinion of the area and improvement under preparing boil.

• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.2148-2150
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• 2014

• Transactions of the Korean hydrogen and new energy society
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• v.27 no.5
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• pp.562-570
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• 2016

At the carbon dioxide capture process using the aqueous amine solution, degradation of absorbents is main factor to reducing the process performance. Also, degradation mechanism of absorbent is important for understanding the environmental risk, route of degradation products, health risk etc. In this study, the degradation products of MEA were studied to clarify mechanism in thermal degradation process. The degradation products were analyzed using a $^1H$ NMR (nuclear magnetic resonance) and $^{13}C$ NMR. The analysis methods used in this study provide guidelines that could be used to develop a degradation inhibitor of absorbent and a corrosion inhibitor.