• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.4
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• pp.11-20
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• 2016

Depletion of natural resources and reduction of greenhouse gas emissions are an important issue which we have to solve. The recycling of waste has emerged as a global concern. In Korea, the development of cost-effective treatment and recycling technologies also need to be improved. In this study, we compared and analyzed the cost per unit of treatment and recycling of organic waste, and presented an effective recycling scheme. We investigated the current status of treatment and costs for six types of organic wastes from 80 workplaces, including organic wastewater treatment sludge, processed organic sludge, and plant residues. In addition, environmental costs for greenhouse gas reduction were calculated. It's an economic way that organic waste is composted and used as cement additives. In particular, the economic analysis was done by realistic results of the survey target companies. In conclusion, in order for reliable processing and recycling of organic wastes, wastewater treatment sludge and sewage sludge need to be classified based on hazard characteristics. Finally, technical difficulties need to be further resolved such as odors, leachate, and debris on recycling organic wastes.

• Applied Chemistry for Engineering
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• v.22 no.2
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• pp.230-234
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• 2011

In this work, the primary material for a single layered hardmask which can afford a spin-on process was prepared by the minture of organic and inorganic sources. The preparation of hybrid polymer was attempted by esterification from silanol terminated siloxane compounds and acetonide-2,2-bis(methoxy)propionic acid. The optical, thermal and morphological properties of the test hardmask film was examined in terms of cross-linking agent and additives. In addition, the etch rate of hardmask film and photo resist layer were compared. The hybrid polymer prepared from organic and inorganic materials was found to be useful for hardmask film to form the nano-patterns.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.772-787
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• 2000

In this study, evaluation on the loaches from the various sources was carried out in respect of their taste compounds. The samples were classified by local, season and growing condition and evaluated in terms of composition, the refuse, contents of nucleotides and their related compounds, total and free amino acid, organic acid and fatty acid. Evaluation on the compositions revealed the fact that, in terms of the local, the imported loach contain a low level of fat and high level of ash, in comparison with Korean loach; in terms of growing condition, cultured loach contains a high level of fat and low level of moisture, in comparison with wild loach; and in terms of the season, the summer loach contains less moisture than the fall loath; but as for the contents of other component, the summer loach was superior. As for the refuse, the imported loach had a greater refuse than the Korean loach. In the growing condition, the wild loach had lower value than the cultured loach. There was no substantial difference in each season. Also nucleotide and these related compounds were detected in all of the samples, while ATP was not found. The content levels of such detected compound did not show a substantial difference in each condition. However, generally, the imported loach was poor in such compound and all of the samples were high in IMP. The samples were high in total amino acids. The local and growing conditions showed no substantial difference, while in the season, the summer loach had a higher content of total and essential amino acid than the fall loach. As for the contents of free amino acids, similar distribution of the composition was shown in each sample, even though there was little difference in their constituents. Also, total content of free amino acid varied with the conditions of the samples. As for total content of organic acid and the distribution of the composition, there was a little difference between each condition. In the season and growing condition, the summer loach was high in organic acid. As for the distribution of the fatty acid compositions, there was no substantial difference between each condition and each sample. In the case of the wild loach, the summer loach was high in ${\omega}-3$ polyunsaturated fatty acid and the fall loach was high in essential fatty acid. Similarly, in the case of the imported loach, the summer loach was high in ${\omega}-3$ polyunsaturated fatty acid and the fall loach was high in essential fatty acid.

• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.3
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• pp.74-84
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• 2002

This experiment was carried out to evaluate supplemental effects of various preservatives to preserve the Brewers grain and Soymilk from decay and degeneration. The NaCl, organic acid(Ca-propionate), microbial fermenter(H/MF inoculant), and methionine hydroxy analogue(MHA) were used as additives in order to compare preservability of brewers grain and soymilk by-product during 20 days at July to August. Most treatments were appeared rapid decay and degeneration as soften and covered with molds on surface from the early days of experiment. However, MHA treatments showed any change until 20 days of storage. In terms of pH and $NH_3-N$ contents, only MHA treatment showed a stable and low value. The other treatments including Control showed high values as time flowed or unstable states. In conclusion, when high moisture agricultural by-product was treated by over 5% of MHA, there was no significant physicochemical changes in long term preservation over 20 days at summer season.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1057-1072
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• 2018

In this study, micro-sized $CeO_2$ particles were synthesized by spray pyrolysis, and EG(ethylene glycol) and CA(citric acid) as organic additives were added to obtain hollow and porous particle during spray pyrolysis, and characteristics of obtained ceria were investigated according to the amount of added organic additives. Spray pyrolysis, postheat and ball-milling were combined to give 6 paths. $CeO_2$ nano-sized particle was obtained by the path which has sequence of Spray Pyrolysis with 0.5 M of EG and CA${\rightarrow}$Post-heat${\rightarrow}$Ball-milling${\rightarrow}$Post-heat among 6 paths. The average particle size(24 nm with standard deviation of 3.8 nm) of $CeO_2$ nano-sized particle by TEM analysis is close to the primary particle size(20 nm) which was calculated by Debye-Scherrer equation. To investigate the morphological characteristics and structure of the synthesized nanoparticle powders, SEM(Scanning Electron Microscopy), XRD(X-Ray Diffractometer) and TEM(Transmission Electron Microscopy) were used.

• Resources Recycling
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• v.27 no.6
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• pp.44-52
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• 2018

In this study, copper was recovered from copper containing sludge by selectively controlling electro-refining process conditions in copper sulfate electrolyte solution. Electro-refining process was performed by LSV (Linear Sweep Voltammetry) result according to copper sulfate electrolyte solution concentration, applied current density, additive type and concentration. SEM (Scanning Electron Microscope) and PSA (Particle Size Analyzer) were used to analyze the shape and size of copper powder. In the 0.1 ~ 0.4 M copper sulfate electrolyte solution without organic additives, the copper powder size decreased as the applied current density became closer to the limiting current density and the copper powder size tended to decrease in 0.2 ~ 0.3 M copper sulfate electrolyte solution. In addition, when the shape and size of the copper powder were analyzed by adding various types and concentrations of organic additives to the previous experimental, fine spherical copper powder having the smallest size (nm) was obtained under the condition of cellulose type additive 2,000 ppm.

• Journal of Practical Agriculture & Fisheries Research
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• v.6 no.1
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• pp.102-115
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• 2004

Main objectives of this study were to increase digestibilities of indigestible ingredients in spent mushroom composts (SMC) consisted of sawdust mainly as well as to fortify conversion of inorganic Se present in SMC to organic Se via fermentable microbial actions. Experimental feeds were designed to contain the increasing level of selenium (0.06ppm, 0.54ppm, 1.26ppm and 1.86ppm) in combination with SMCs of Se-enriched and non-Se mushrooms. Feeds were also fermented using commercial microbial feed additives (Sambae, Ltd., Korea) comprised Saccharomyces, Bacillus, Aspergillus, Streptococcus and Actinomycetes before feeding trial for Hanwoo (Korean native cattle). Those were fermented for 0, 12, 24, and 48 hrs. Initial pH was linearly increased as Se concentration increases or the proportion of SMC of Se-enriched mushroom increased (p<0.0001). pH values of fermented feeds (0.54ppm, 1.26ppm and 1.86ppm) containing SMC of Se-enriched mushroom were not different since 12 hrs of fermentation time and their pH was significantly lowered compared to control group. The increasing level of Se concentration in fermented feeds showed significant differences in organic and inorganic Se contents and proportion of organic Se among treatments. As a SMC proportion of Se-enriched mushrooms in the fermented feed was increased, organic Se proportion was significantly decreased (p<0.0001). The control treatment (0.06ppm) comprising the non-Se SMC only was estimated of the organic Se to be 100% and the treatment groups containing the increasing level of Se were estimated of organic Se to be approximately 70%.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1206-1209
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• 2006

Carbon nanotubes (CNTs) have been significantly used for the field emitters for display applications. However, the lifetime of CNT emitters which are formed by screen printing technique is not guaranteed yet, because the constituents in CNT paste affect the lifetime of CNTs. The CNT pastes for screen printing are normally composed of organic vehicles (nitro cellulose, ethyl cellulose, etc) and additives (glass frits, ITO, etc) with CNTs. In this study, the effects of constituents in CNT pastes on the lifetime and emission characteristics of CNTs were investigated by thermal and electrical analysis. Use of glass frits worsened the lifetime and electron emission of CNTs. However, an addition of ITO to CNT paste rather improved the lifetime of CNTs. Degradation of CNTs was small when nitro cellulose was used in CNT paste as an organic vehicle.

• Journal of the Microelectronics and Packaging Society
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• v.23 no.4
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• pp.79-85
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• 2016

It is imperative to find environment-friendly coatings as an alternative to the currently used hexavalent chromate conversion coatings for the purpose of improving the anti-corrosion properties of aluminum alloys. Hence, in this study, the corrosion properties of a trivalent chromate conversion coating solution are analyzed and measured. Because of the presence of multiple components in trivalent chromate conversion coating solutions, it is difficult to control plating, attributed to their mutual organic relationship. It is of significance to determine the concentrations of the components present in these coatings; hence, qualitative and quantitative analysis is required. The coating solution contained not only an environment-friendly component chromium(III), but also zirconium, fluorine, sulfur, and potassium, in the coating film. These metals are confirmed to produce a film with improved corrosion resistance to form a thin layer. The excellent corrosion resistance for the trivalent chromate solution is attributed to various inorganic and organic additives.

• Korean Journal of Organic Agriculture
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• v.19 no.4
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• pp.589-602
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• 2011

In this study, experiments were conducted to determine the effect of different compost teas on plant growth reponses and yield of leaf lettuce. Compost tea is a liquid extract of compost obtained by mixing compost and water for a defined period of time. The pig manure and spent mushroom compost were made by steeping compost in water. Compost tea was aerated from 24 hours and molasses and kelp were added as supplements. The four types of compost were tested growth of lettuce. EC of animal manure compost tea was higher than that of spent mushroom compost tea. Mineral nutrients were significantly higher in animal manure compost tea compared with spent mushroom compost tea. Compost tea contains nutrient and a ranges of different organisms. The beneficial fungi and actinomycetes were prominent in a spent mushroom compost tea. Compost tea from animal manure had the higher numbers of total bacteria. The actinomycetes densities were high in spent mushroom compost tea. But actinomycetes were not founded in animal manure compost tea. The growth characteristics of lettuce in animal manure compost tea were higher than those of spent mushroom compost tea. And also SPAD value in leaf was high in plot treated with animal manure compost tea. The fresh yield of lettuce in animal compost tea was higher by 181% that of control plot. The effect of compost tea on growth of lettuce was largely attributable to mineral nutrient.