• Carbon letters
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• v.13 no.4
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• pp.191-204
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• 2012

Carbon nanotubes (CNTs) have exceptional mechanical, electrical, and thermal properties compared with those of commercialized high-performance fibers. For use in the form of fabrics that can maintain such properties, individual CNTs should be held together in fibers or made into yarns twisted out of the fibers. Typical methods that are used for such purposes include (a) surfactant-based coagulation spinning, which injects a polymeric binder between CNTs to form fibers; (b) liquid-crystalline spinning, which uses the nature of CNTs to form liquid crystals under certain conditions; (c) direct spinning, which can produce CNT fibers or yarns at the same time as synthesis by introducing a carbon source into a vertical furnace; and (d) forest spinning, which draws and twists CNTs grown vertically on a substrate. However, it is difficult for those CNT fibers to express the excellent properties of individual CNTs as they are. As solutions to this problem, post-treatment processes are under development for improving the production process of CNT fibers or enhancing their properties. This paper discusses the recent methods of fabricating CNT fibers and examines some post-treatment processes for property enhancement and their applications.

• Korean Journal of Organic Agriculture
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• v.18 no.2
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• pp.155-176
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• 2010

This study was conducted to research the status, history and prospects of farm scale milk processing and to develop a management strategy for small scale milk process plant in Korea. Also it aims to provide ways to apply it so as to vitalize the farm made milk products market practically. This study was also treats the practical development of dairy farm school programs through the farm scale milk processing. Farm-scale milk plant (FMP) should be some of the ideas to develop small scale and using the resources according to the local features, limited expanding in regional market, produce by consumers order amounts, management policy will be transferred organic dairy farm. A few policy suggestions to put FMP system of financial support would not from beginner, it is better to settled FMP system by government or co-operation group in practical support programs were proposed. What the state needs to do through direct involvement were to put efforts at demand expansion on FMP system products, to certificate and safety the farm made milk products marketing system settings, to build more variation chance of the milk products. What was more important, however, was support policy, to create the network of FMP market and to develop of training program contents for each FMP operation unit. The ideal FMP model for the development of Dairy Farming proposed in this research will be applied as a relevant reference in managing and realizing environmental friendly and sustainable dairy industry at the national level.

• Environmental Engineering Research
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• v.23 no.4
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• pp.345-353
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• 2018

This paper summarizes results of research on the electrochemical (EC) degradation of disinfection by-products (DBPs) and iodine-containing contrast media (ICMs), with the focus on EC reductive dehalogenation. The efficiency of EC dehalogenation of DBPs increases with the number of halogen atoms in an individual DBP species. EC reductive cleavage of bromine from parent DBPs is faster than that of chlorine. EC data and quantum chemical modeling indicate that the EC reduction of iodine-containing DBPs (I-DBPs) is characterized by the formation of active iodine that reacts with the organic substrate. The occurrence of ICMs has attracted attention due to their association with the generation of I-DBPs. Indirect EC oxidation of ICMs using anodes that produce reactive oxygen species can result in a complete degradation of these compounds yet I-DBPs are formed in the process. Reductive EC deiodination of ICMs is rapid and its overall rate is diffusion-controlled yet I-DBPs are also produced in this reaction. Further progress in practically feasible EC methods to remove DBPs, ICMs and other trace-level organic contaminants requires the development of novel electrocatalytic materials, elimination of mass transfer limitations via innovative design of 3D electrodes and EC reactors, and further progress in the understanding of intrinsic mechanisms of EC reactions of DBPs and TrOC at EC interfaces.

• Journal of Life Science
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• v.27 no.10
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• pp.1176-1184
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• 2017

The contents of inorganic and functional components in the organic Cheongyang pepper, tomato, and strawberry were compared with those of the conventional produce. The analyzed functional components were total phenol, total flavonoid, vitamin C, vitamin E, ${\beta}-carotene$, and capsaicin in Cheongyang peppers; lycopene in tomatoes; and anthocyanin in strawberries. The analyzed inorganic components were total N, Zn, Fe, Ca, Mg, Na, K, and P. The total phenol contents of Cheongyang peppers and tomatoes were 14% and 30% higher, respectively, in the organic vegetables than the conventional ones, whereas strawberries had 13% higher components than the conventional ones. The total flavonoid contents of the Cheongyang peppers and tomatoes were 11% and 29% higher, respectively, than in the conventional produce, but those of the strawberries were 100% higher than in conventional strawberries. Vitamins were mostly higher in organic cultivation products, but there was no significant difference. The ${\beta}-carotene$ content was 22% higher in organic tomatoes, but conventional strawberries and peppers had more ${\beta}-carotene$ than the organic types did. The contents of capsaicin and lycopene were no different between the various cultivations, while anthocyanin was higher in the conventional cultivation. Analysis of inorganic components did not differ between cultivation methods for peppers and tomatoes, and the total N, K, and P contents were higher by 20-28% in the conventional cultivation. The contents of K, Ca, Mg, and P were 16-29% higher in the conventional cultivation of strawberries. Depending on the crops, there were many syntheses of functional components in the organic cultivation. This was thought to be due to nutrients and environmental stress.

• Proceedings of the Membrane Society of Korea Conference
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• 1993.10a
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• pp.46-51
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• 1993

Poly(vinyl chloride) was modified by reacting with sodium N-methyldithiocarbamate or N-methyl-N-carboxymethyldithiocarbamate to obtain crosslinked dithiocarbamated PVC(PMD, PSDC). In addition PSDC were substituted with metal ions of $Ma^+, Li^+$ and $Cs^+$. PLMD and PSDC were reacted with copper ions in alcohol or aqueous solution to produce chelate complexes of dithiocarbanated PVC, respectively(PMD-$Cu^{2+}$, PSDC-$Cu^{2+}$). PSDC was irradiated by ultraviolet light to enhance crosslinking(PSDC-UV).

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.10a
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• pp.1.2-1.2
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• 2011

Electrohydrodynamics is a good approach to produce uniform-sized colloids and fibers in a continuous process. The dimension can be controlled from tens of nanometers to a few micrometers. The structure of the colloids and nanofibers from electrohydrodynamics has been diversified according to the uses. Especially, core-shell structure and hybridization with functional nanomaterials are fascinating due to their possible uses in drug-delivery systems, multifunctional scaffolds, organic/inorganic hybrids with new functions, and highly sensitive gas- or bio-sensors. This talk will present the structural variations in the colloids and fibers by simply employing phase separation during electrohydrodynamic process and demonstrate their possible applications.

• YAKHAK HOEJI
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• v.29 no.4
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• pp.220-222
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• 1985

Rifampicin reacts with cupric ion to produce rifampicin-Cu(II) chelate (2:1) at pH 6.5, which can be extracted with methylisobutylketone (MIBK). Therefore, rifampicin can be quantitatively, determined by measuring the quantity of Cu(II) in the organic phase by atomic absorption spectrophotometry. Because higher absorbance ratio was obtained in pH 6.0~7.0, buffer solution at pH 6.5 was used in this measurement. Linear relationship was found between absorbance and concentration in the range of 1.0~4.0${\times}10^{-4}M$. This method might be applicable to the determination of rifampicin in the preparations.

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05a
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• pp.25-28
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• 2004

In recent years, membranes have become fully or partially integrated into all facilities that produce drinking water since membrane processes can resolve technically complex and, at times, conflicting requirements related to compliance with multi-contaminant regulations. However, NF or RO technologies are hydraulically limited by the feed water quality that causes the fouling in a membrane system. In particular, NF or RO systems involved in surface water treatment generally require extensive pretreatment for controlling membrane fouling.(omitted)

• Korean Journal of Organic Agriculture
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• v.22 no.3
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• pp.423-434
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• 2014

This study was conducted to investigate the hypoglycemic effects and the production conditions of the Korean organic native rice cultured by Ganoderma lucidum. The broth culture of Ganoderma lucidum, the innoculation and culture of Ganoderma lucidum to the Korean organic native rice, and the oral administration of the Korean organic native rice cultured by Ganoderma lucidum to the streptozotocin-induced diabetic rats, were carried out. Then, the blood glucose level, the serum total cholesterol and triglyceride, and the activities of alanine aminotransferase and aspartate aminotransferase, were analyzed. The pH 4.5 at $30^{\circ}C$ was the optimal condition of the broth culture of Ganoderma lucidum. When the physical shape and the smell of the produced rice were considered, the optimal conditions to produce the Korean organic native rice cultured by Ganoderma lucidum, were the seeding of Ganoderma lucidum to Korean organic native rice in the rate of 7.5% weight, and the culture period of 9days at $28^{\circ}C$. In streptozotocin-induced diabetic rats, the blood glucose level of the dieted group by the Korean organic native rice cultured by Ganoderma lucidum for 2 weeks, were significantly decreased when compared with the control. And, the levels of the total cholesterol and triglyceride in serum were ranked less than those of the control. Also, in streptozotocin-induced diabetic rats, the activities of alanine aminotransferase and aspartate aminotransferase in the serum of the dieted group by the Korean organic native rice cultured by Ganoderma lucidum for 2 weeks, were lower than those of the control.

• Journal of the Korean Electrochemical Society
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• v.19 no.4
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• pp.141-147
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• 2016

In this study, homo and copolymers of 2,2,6,6-tetramethyl-4-piperidyl methacrylate(TMA) and synthesized styrene derivative, 2,2,6,6-tetramethylpiperidine-4-vinylbenzyl ether(TVBE) were obtained by radical polymerization and oxidized to produce corresponding polymer radicals. The polymer radicals were mixed with carbon black, binders and coated onto Al current collector. The battery performance is then characterized by fabricating coin cells. As results, the polystyrene based organic radicals show lower oxidize efficiency and discharge capacity than methacrylate based one. However, the former shows better capacities from discharge experiments performed at $60^{\circ}C$ which suggests a possible way to overcome the high temperature fade out of performance in usual organic radical batteries. Also as expected, an excellent C-rate performance is observed in all the cells consisted of organic polymer radicals.