• Fisheries and Aquatic Sciences
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• v.15 no.4
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• pp.275-281
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• 2012

Yellow croaker Larimichthys polyactis muscle oil was extracted using an environmental friendly solvent, supercritical carbon dioxide (SC-$CO_2$), in a semi-batch flow extraction process. SC-$CO_2$ was applied at temperature $35^{\circ}C$ to $45^{\circ}C$ and $150^{\circ}C$ to $250^{\circ}C$ bar of pressure. The flow rate of $CO_2$ (27.79 g/min) was constant throughout the entire 1.5 h extraction period. The oil extraction yield was influenced by the physical properties of SC-$CO_2$ at different temperatures and pressures. The extracted oil was analyzed by gas chromatography to determine the fatty acid composition. According to our results, the SC-$CO_2$ extracted oil was high in eicosapentaenoic acid and docosahexaenoic acid. In addition, the SC-$CO_2$ extracted oil showed greater stability than n-hexane extracted oil based on the peroxide value and acid value. Thus, the quality of yellow croaker oil obtained by SC-$CO_2$ extraction was slightly higher than that of oil obtained by n-hexane extraction.

• BMB Reports
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• v.36 no.6
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• pp.597-602
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• 2003

Acid phosphatases (APases) play a role in the release of phosphate in organic complexes in soil. We investigated tissue- and isoform-specific responses of APases to phosphorus (P) deficiency in three rice genotypes; Dasan-byeo, Sobi-byeo, and Palawan. The levels of shoot APase activity per protein were similar in the three genotypes. They significantly decreased with P deprivation that was longer than seven days. Root APase activity per protein was two- to three-fold higher in Dasan than in Sobi and Palawan. In all genotypes the APase activity increased in P-deficient plants, but the increase was higher in Sobi and Palawan. After 21 days of P deprivation, secreted APase activity increased more than eight-fold in Dasan and two-fold in Sobi and Palawan. Isoform profiles of shoot and root APases were most diverse in Dasan. The activities of the major isoforms in P-deficient shoots decreased in all three genotypes. Depending on the genotypes, further increases in constitutive isoforms and new induction of one to four isoforms occurred in P-deficient roots. The results indicate that tissue and genotype differences in the response of APase to P deficiency are primarily facilitated by the different responses of the isoforms.

• KIEAE Journal
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• v.4 no.2
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• pp.49-56
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• 2004

This study intends to propose the fundamentals of 'Ecovillage' design by researching into the cycle system of material of 'Crystalwaters' which is having been in charge of a leading role of GEN since 1996 (GEN was formed in 1996) as Ecovillage in Australia. First, to secure the water resources, we can store up rain and the water of valley, and dam. Second, we are able to use the natural filter apparatus, do tree-planting of roof to gain better quality of water. Third, it is to save the energy as supplying water. For it, we make the best of a gravity that is one of the cycle principle of water. Forth, to build a Dam can make a site of scenic beauty, do the role of recreation place and provide against emergencies (a fire, drought) as well as make a mild climate. Fifth, it can reduce the environment load because of sewage and garbage as making it compost. This is possible by treating biologically using composting apparatus of the dry or wet process. Sixth, it is to reduce the environmental pollution as to discharge seperating a recycable waste, an organic matter being able to make it compost. Finally, first of all, environmentally friendly inhabitant consciousness from lifestyle and production style plays an importent part for water cycle and the ecological cycle of waste and sewage.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.6
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• pp.1739-1744
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• 2008

Non-toxic orgarnic inorgarnic complex green pigment using Fluidized Bed Vapor Deposition(FB-VD) process was developed to alternate green pigment used heavy metals chrome and lead in present domestic. Kaolin materials and $CaCO_3$ were used as supporter of pigment and surface and compositions of supporters were characterized by SEM and EDXS, respectively. Various kind of surface active agents(surfactants) were also used to optimize the dry condition or color revelation. Results showed that anion type surfactant is most suitable for dry and color revelation of pigment.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.5
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• pp.62-66
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• 2010

Cellulosic materials were dissolved by NMMO(N-methylmorpholine-N-oxide) and CED (Cupriethylene diamine), respectively, to measure their DPs (degrees of polymerization) by using viscometer. We changed cellulose DPs by applying various amounts of low intensity electron-beam radiation to the cellulosic materials. NMMO is environmental-friendly, non-toxic, and biodegradable organic cellulose solvent and used industrially because of its high cellulose dissolving power and high solvent recovery ratio. The cellulose DP measurement results using these two different chemicals were correlated highly ($R^2$ >0.95). It was also found that cellulose with high DP was dissolved more easily in NMMO than CED. In addition, NMMO method gave more higher resolution in the measurement.

• Composites Research
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• v.36 no.4
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• pp.264-269
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• 2023

Spent coffee grounds (SCG) are a ubiquitous byproduct of coffee consumption, representing a significant waste management challenge, as well as an untapped resource for economic development and sustainability. Improper disposal of SCG can result in environmental problems such as methane emissions and leachate production. This study aims to investigate the physicochemical properties of SCG and their potential as a reinforcement material in polypropylene (PP) to fabricate an eco-friendly composite via extrusion and injection molding, with SCG filler ratios ranging from 5-20%. To evaluate the effect of SCG on the morphological and mechanical properties of the bio- composite, thermogravimetric analysis, SEM, tensile, flexural, and impact tests were conducted. The results demonstrated that the addition of SCG lead to a slight increase in brittleness of the composite but did not significantly affect its mechanical properties. Impressively, the presence of a significant organic component in SCG contributed to the enhanced thermal performance of PP/SCG composites. This improvement was evident in terms of increased thermal stability, delayed onset of degradation, and higher maximum degradation temperature as compared to pure PP. These findings suggest that SCG has potential as a filler material for PP composites, with the ability to enhance the material's properties without compromising overall performance.

• Korean Journal of Organic Agriculture
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• v.9 no.1
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• pp.51-60
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• 2001

An experiment was carried out to evaluate the effects of adding phytase on nutrient digestibility in growing pigs. Three barrow pigs averaging 28.5$\pm$3.1kg of body weight were allotted to three treatments by 3$\times$3 latin square. Treatments included 1) com-soybean meal based-control diet and 2) and 3) control diet with phytase 500 and 1,000 unit. There were no effects of treatments on dry matter and nitrogen digestibility (P〉0.05). Ash, Ca and P digestibility in pigs fed diet with phytase were greater than those in pigs fed control diet(P〈0.05). An increased phosphorus intake was observed from pigs fed diet with treatments compared to that from pigs fed control diet. Pigs fed diet with adding phytase had improved P absorption compared to pigs fed control diet(P〈0.05). There was no significantly effect on fecal and urine excretion(P〈0.05). Ca intake was increased for pigs fed adding phytase compared to pigs fed control diet. No evident effect was observed on Ca fecal excretion among dietary treatments, however, urine excretion of pigs fed diet with treatments was decreased compared to pigs fed control diet. Cystine, isoleucine, tyrosine and phenylalanine digestibility of amino acid were greater for pigs fed diet with treatments than those for pigs fed control diet(P〈0.05). Asparagine, threonine, serine, methionine and leucine digestibility were improved for pigs fed with phytase 500 unit compared to pigs fed control diet. Lysine, histidine, arginine and other animo acids digestibility were higher for pigs fed diet with phytase than control diet, but there were no significant effects by the treatments(P〉0.05). In conclusion, the results of the experiments suggest that phytase supplementation in the diets could be a very beneficial strategy in environmental aspects.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.1
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• pp.51-57
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• 2016

This study is conducted to find out the problems of the public food waste recycling facility operation and its improvement. In order to save the national budget by analyzing plans to expand including operation rate for the food waste recycling facility, the alternative ways are suggested. The result can be as follows: Policy switch is required not only to save budget and stable disposal of food waste but also to promote resource recycling rather than expanding public facilities. In order to change the policy for stable and eco-friendly disposal of food waste, it is necessary to adopt semipublic system that prevent the decline of the rate of operation of private resource recycling facility. Furthermore, it is required to prepare both qualified technologies of public resource recycling and the ways of profitability secure.

• Journal of the Korean Applied Science and Technology
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• v.32 no.3
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• pp.512-521
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• 2015

In this research, environmental friendly organic acid containing microetching system to improve adhesion strength between photoresist resin and Copper Clad Laminate(CCL) was developed without using strong oxidant $H_2O_2$. Etching rate and surface contamination on CCL were examined with various etching conditions with different etchants, organic acids and additives. to develope an optimum microetching condition. Etching solution with 0.04 M acetic acid showed the highest etching rate $0.4{\mu}m/min$. Etching solution with the higher concentration of APS showed the higher etching rate but surface contamination on CCL is very serious. In addition, stabilizer solution also played an important role to control the surface contamination. As a result of research, the etching solution containing 0.04 M of acetic acid, 0.1 M of APS with 4 g/L of stabilizer solution(ST-1) was best to improve adhesion between CCL and photoresist resin as well as showed the most clean and rough surface with the etching rate of $0.37{\mu}m/min$.

• Membrane Journal
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• v.29 no.6
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• pp.299-307
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• 2019

Photocatalysis is an environment friendly technique for degrading organic dyes in water. Tungsten oxide is becoming an active area of research in photocatalysis nanomaterials for having a smaller bandgap than the previously favored titanium dioxide. Synthesis of hierarchical structures, doping platinum (Pt), coupling with nanocomposites or other semiconductors are investigated as valid methods of improving the photocatalytic degradation efficiency. These impact the reaction by creating a redshift in the wavelength of light used, effecting charge transfer, and the formation/recombination of electron-hole pairs. Each of the methods mentioned above are investigated in terms of synthesis and photocatalytic efficiency, with the simplest being modification on the morphology of tungsten oxide, since it does not need synthesis of other materials, and the most efficient in photocatalytic degradation being complex coupling of metal oxides and carbon composites. The photocatalysis technology can be incorporated with water purification membrane by modularization process and applied to advanced water treatment system.