• Applied Chemistry for Engineering
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• v.3 no.2
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• pp.288-295
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• 1992

The reduction of nitrobenzene by triirondodecacarbonyl over phase transfer catalysts was investigated. The phase transfer catalysts showed a good yield of aniline at room temperature. Benzyltriethylammonium chloride, tricaprylmethyl ammonium chloride, 18-crown-6 and polyethyleneglycol-400 were good phase transfer catalysts in this reaction. The effect of reaction temperature, concentration of sodium hydroxide and organic solvents on the reaction rate and yield of aniline were studied in this work.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.4
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• pp.412-418
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• 2007

The purpose of this study was to determine the several factors for affecting chlorine disinfection by-products(DBPs) characteristics by reacting chlorine and organic matters in the aquatic phase. The results of this research yield the following specific conclusions: The concentration of trihalomethanes(THMs) was increased with increasing dissolved organic carbon(DOC), and a trend of THMs formation was parabolic with increasing organic matters. Formations of THMs increased straightly for the first 4 hours and the amounts of producted THMs for the 30 minutes were up to $25\sim43%$ in the entire experiment periods(168 hours). When keeping up the concentration of organic matters at constant and changing that of bromide, the quantity of formed THMs did not show distinguished difference with the reaction times. THMs were gradually increased at $4^{\circ}C$ even though a reaction phase was parabolic formation(PF) phase. However, THMs were increased rapidly in the instantaneous formation(IF) phase and then became slowdown in the PF phase between $20\sim35^{\circ}C$. THMs were gradually increased although entering in the PF phase at pH 5. However, THMswere increased rapidly in the IF phase and then became slowdown in the PF phase at pH 7 and pH 9, and these treads were much more clear at pH 9 than at pH 7.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1659-1664
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• 2014

A porous metal-organic framework (MOF), MIL-101, was synthesized in the presence of sulfated zirconia (SZ) to produce acidic SZ/MIL-101 composites for the first time. The composites were characterized with XRD, nitrogen adsorption, FT-IR, scanning electron microscope, chemical analysis and so on. The composites (SZ/MIL-101s) were successfully applied in a liquid-phase esterification for a high yield of ester. This catalytic result of SZ/MIL-101, compared with that of pure SZ or MIL-101 (showing a negligible yield of ester), suggests that the SZ in the composite is highly active in the acid catalysis probably because of the well-dispersed active species of SZ. Moreover, the esterification is catalyzed in heterogeneous mode as confirmed by negligible esterification after filtration of the catalyst. Finally, microwaves can be efficiently applied both in the synthesis of the composites and the esterification reaction to accelerate the two processes of synthesis and esterification by about 5 times.

• Journal of Environmental Science International
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• v.31 no.12
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• pp.1127-1134
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• 2022

Herein , the effect of changes in the organic loading rate in anaerobic digestion was evaluated. The experiment was carried out by a laboratory -scale semi-continuous stirred tank reactor, and feedstock was food-waste leached. The organic loading rate was increased by 0.5 kgVS/m3 in each phase from 1.0 kgVS/m3 to 4.0 kgVS/m3. At the end of the operation, to check the failure of the reactor, the organic loading rate was increased by 1.0 kgVS/m3 in each phase and reached 6.0 kgVS/m3. This shows that the biogas yield decreased as organic loading rate increased. Biogas production seemed to be unstable at 3.5-6.0 kgVS/m3. Moreover, biogas production dramatically fell to approximately 0 mL at 6.0 kgVS/m3, which was decided as the operation failure on the 16th day of the las tphase. The result of the reactor analysis shows that the cumulation of volatile fatty acid increased as the organic loading rate increased. This seems to occur due to the decreasein pH in the reactor and led to extinction of anaerobic bacteria, which were the biogas products. Although the buffer compound (alkalinity) could prevent the decline in pH, the concentration of alkalinity was found to be lacking at a high organic loading rate

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.196-199
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• 2003

This experiment was conducted to evaluate the differences in physicochemical properties of soil, grain yield and milling recovery ratio and grain appearance of rice grown in long-term no-till and ordinary till systems. The paddy in no-till rice system was unploughed but straw-mulched for 15 years from 1988 to 2002 at the Experimental Paddy of Gyeongnam Agricultural Research and Extension Services, while the paddy in ordinary till system was ploughed and puddled every crop year, A 5cm organic layer was formed in 11-year no-till rice system, in which exchangeable cation and phosphate were accumulated. In no-till paddy organic matter, bulk density and solid phase of surface soil significantly increased, while pH, exchangeable cation, phosphate, liquid and gaseous phase decreased. Tillage made the very top soil soft, but made deep soil below 5cm significantly hard. In the 1st year of no-till, topsoil showed hard, but in the process of the time in no-till system, the top- and sub-soil showed softer, Yield and yield components of rice showed no differences between till- and no-till rice systems. Milling recovery ratio and grain appearance were not significantly different between no-till and till-rice systems.

• Membrane and Water Treatment
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• v.6 no.4
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• pp.277-292
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• 2015

The extraction of lactic acid by an emulsion liquid membrane (ELM), in batch and continuous mode, has been reported. On the basis of preliminary experiments, the optimum composition of the organic phase (membrane) is determined. When the SPan 80 is used as surfactant, the emulsion breakage exceeds 50%, but only 10% is obtained when the ECA4360 is used. The effects of surfactant, carrier and solute concentrations, phase volume ratio, and stirring speed on the extraction yield were examined and optimized. Surfactant, carrier and diluent used were ECA4360, trilaurylamine (TLA) and dodecane, respectively; 2-ethylhexane-1,3-diol (EHD) is used as a co-surfactant. Under optimal conditions, emulsion breaking is very low and the swelling is kept at its lowest level. Under the pH conditions of fermentation medium, the extraction yield is lower. A mixer-settler continuous system was used for testing these conditions. The residence time, the number of extraction stages and the stability of the emulsion were studied and optimized. The extraction yield obtained exceeds 90%.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.53-53
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• 2010

The development of synthetic pathway to produce a highly yield nanoparticles is an important aspect of industrial technology. Herein, we report a simple, rapid approach to synthesize organic-soluble Cu and Ag nanoparticles in colloidal method for the application in a conductive pattern using inkjet printing. The silver nanoparticles have been synthesized in highly concentrated organic phase. The Cu nanoparticles have been synthesized by the reducing of the copper oxide materials using acid molecules in high concentrated organic phase. Their sintering and electric conductivity properties were investigated by melting process between $200^{\circ}C$ and $250^{\circ}C$ for application to printed electronics.

• Journal of Microbiology and Biotechnology
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• v.7 no.4
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• pp.258-261
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• 1997

For the efficient production of lysophospholipid the hydrolysis of phospholipid using phospholipase $A_1$ from Serratia sp. MK1 was studied in an aqueous-solvent, a two-phase and an emulsion system. Judged on the basis of productivity and the degree of hydrolysis, the yield of lysophospholipid in a two-phase system was found to be better than that obtained in an emulsion system. Among the 13 organic solvents tested phospholipase $A_1$ showed the most efficient catalytic activity and stability in butyl acetate. When 20% phospholipid was used it was completely hydrolyzed in this two-phase system.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.4
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• pp.15-22
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• 2017

Application of organic resources to agricultural land can increase crop yield by improving soil characteristics. The objective of this study was to evaluate effect of crop yield and soil physical properties including aggregate stability to application of organic resources in upland. The soybean was cultivated in a sandy loam field and a clay loam field located at Suwon and a sandy loam field located at Pyeongchang. The organic resources used in this study were rice straw compost (RSC), composted pig manure with sawdust (CPIG), composted poultry manure with sawdust (CPM), and cocopeat applied before sowing crop. Application rate of organic resources was determined based on carbon content and water content. The inorganic fertilizers were applied based on soil testing. In addition, the decomposition of RSC, CPIG, and cocopeat was characterized by isothermal incubation with sandy loam soil. The decomposition rate was highest for RSC followed by CPIG and cocopeat. Organic resource application increased yield of soybean, which effect was greater in clay loam than in sandy loam. In addition, increase in gas phase proportion by organic resource application was distinct in clay loam soil compared with sandy loam soil. In terms of aggregate stability, increasing effect was more obvious in sandy loam soils than in a clay loam soil. The highest yield was observed in RSC treatment plots for all the fields. Improvement of soybean yield and soil physical characteristics by cocopeat was not as much as that of the other organic resources. The results implied that RSC could be recommended for promoting aggregate stability and crop yield in upland cultivation.

• International Journal of Internet, Broadcasting and Communication
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• v.7 no.2
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• pp.155-160
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• 2015

The objective of this study was to develop the classification method of various organic wastes. Specifically, the effects of proximate composition on the biogas production and degradation rates of agricultural by-production was investigated and a new standards for mixture of various organic wastes based on proximate composition combination was developed. Agricultural by-products (ABPs) with medium total carbohydrate, medium crude protein and low fat contents demonstrated the single step digestion process. ABPs with low total carbohydrate, high crude protein and high fat contents demonstrated the two step digestion process of Diauxic growth. The single ABP (Class No. 15) and the mixed ABPs (Class No. 12+18, 6+12+22, 9+12+18) after 10days showed the similar biogas yield pattern. We can use the classification method for the more ABPs and organic wastes from factory and municipal waste treatment plant for the high efficient biogas production.