• Environmental Engineering Research
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• v.20 no.1
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• pp.99-104
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• 2015

The purpose of this study is to evaluate the performance of forward osmosis (FO) system for harvesting microalgae cultivated in secondary sewage effluent. Microalgae species used in this study were chlorella sp. ADE4. The drawing agents used for forward osmosis system were seawater and concentrate of sea water reverse osmosis (SWRO) system. Chlorella sp. ADE4 cultured in secondary sewage effluent illustrated moderate efficiency in removal of total nitrogen (TN) (68%) and superior performance in total phosphorus (TP) removal (99%). Comparison of seawater and SWRO concentrate as drawing agent were made in FO membrane separation of the microalgae. The result from this study depicts that SWRO concentrate is strong drawing agent in FO membrane system providing an average dewatering rate of $4.8L/(m^2{\cdot}hr)$ compared to seawater with average dewatering of $2.9L/(m^2{\cdot}hr)$. Results obtained from this study indicated that FO system could be viable option for harvesting the microalgae for further biodiesel production. SWRO concentrate as a drawing agent could be very important finding in field of membrane technology for disposal of SWRO concentrate.

• Journal of Adhesion and Interface
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• v.17 no.2
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• pp.49-55
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• 2016

In this study, we designed an environment friendly, water-based adhesive using the acrylic emulsion method as a replacement for solvent-based adhesives, which are most commonly used in layered laminates for flexible food packaging. We designed adhesives with different combinations of anionic, non-ionic, and phosphoric ester surfactants, and with different concentrations of chain transfer agent (CTA). We also examined the effect of the degree of cross-linking by synthesizing and comparing 8 test group adhesives with different types of functional monomers. Additionally, we synthesized 2 other test group pressure-sensitive adhesives (PSA) using styrene/alpha-methyl styrene/acrylic acid (SAA) semipolymer dispersing agents (with molecular weights of 13,000 g/mol and 8,600 g/mol, respectively) to replace the conventional surfactants. We evaluated whether the 10 test group pressure-sensitive adhesives met the basic physical property criteria required for flexible food packaging by carrying out a physical analysis of their glass transition temperature (Tg), particle size, adhesion, and molecular weight. In our test, 2 test group adhesives manufactured with the combination of anionic and non-ionic surfactants, CTA concentration of 0.2%, and functional monomers of hydroxyethyl acrylate (HEA) and glycidyl methacrylate (GMA) demonstrated molecular weight and flexibility suitable for flexible packaging, with low adhesiveness and small particle size.

• Korean Journal of Environmental Agriculture
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• v.40 no.4
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• pp.322-329
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• 2021

BACKGROUND: The fungicide of benomyl, a benzimidazole group, has been commonly used for pesticides against fungal diseases in the world. However, benomyl is rapidly hydrolyzed in the environment after using to control plant diseases and has adverse effects by generating carbendazim, which is toxic to plants, humans, and the environment. METHODS AND RESULTS: In this study, the decomposition effect of carbendazim, a degradation product of benomyl was conducted in pot and field after making a prototype of benomyl-degrading microbial agent (BDMA). We found that the carbendazim-degrading microbial agent (CDMA) (10⁵, 10⁶, and 10⁷ cfu/g soil) decomposed carbendazim by 50% or more in all the treatments, compared to the untreated control in the pot tests after four weeks. The effect of 100% decomposition of carbendazim was observed at 7 days after treatment, when the prototype of BDMA was apllied at 10-folds dilution in the field. The decomposition effect at more than 60% and plant growth promoting effect were observed after 7 days of the treatment, compared with the untreated group in the second field experiment,treated with commercially available concentrations of 500-folds and 1,000-folds. CONCLUSION(S): These results might represent that the BDMA would decompose carbendazim effectively, a decomposition product of the fungicide benomyl, remaining in agricultural area, and it could be utilized practically by using a low dilution rate.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.4
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• pp.366-373
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• 2015

Construction waste is recycled and used for the efficient and eco-friendly disposal of construction waste increasing due to reconstruction and redevelopment project and so on. There is recycled aggregate as a typical case. And this recycled aggregate shows strong alkalinity due to calcium hydroxide, and causes many environmental problems. Therefore, this is a study on reduction in the strong alkalinity of recycled aggregate by using sodium phosphate based ammonium in order to reduce the pH of recycled aggregate. Besides, a possibility that a pH reducing agent of recycled aggregate could be applied to a site was evaluated. As a result, it was possible to verify that pH decreased as the percentage of pH reducing agent increased. It is thought that the pH reducing agent can be applied to a site by methods such as immersion and spray using the pH reducing agent in the process of producing recycled aggregates.

• Korean Chemical Engineering Research
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• v.57 no.1
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• pp.22-27
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• 2019

Nail polish is used to decorate nail beautifully however, it contains lots of toxic materials. Generally, Nail polish consists of film-forming agent, colorant, solvent, surfactant and stabilizer. In this study, to replace toxic chemicals to low irritative, eco-friendly ingredients, we prepared 4 kinds of nail polish and tested safety, stability and performance. Nail polish including shellac/gelatin showed best performance in water-resistance, friability and drying time. When cell toxicity test is done by MTT assay, shellac-gelatin nail polish showed over 70% cell viability at $1,000{\mu}g/mL$ whereas control nail polish in market showed 50% cell viability. At 4 weeks temperature stability test, color was stable at low temperature however it needs formulation improvement at higher temperature.

• Research in Plant Disease
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• v.25 no.1
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• pp.33-37
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• 2019

From 2016 to 2018, approximately 15% of kohlrabi were observed displaying significant clubroot symptoms in farmer's fields in Jeju, Korea. The initial infection appeared as hypertrophy of root hairs, and as the disease progressed, galls formation occurred on the main roots, finally disease progress resulted in yellowing and wilting of leaves. Pathogenicity was proven by artificial inoculation of plants with resting spore suspension, fulfilling Koch's postulates. The resting spore is one-celled, spherical and subspherical, colorless, and $3-5{\mu}m$ in diameter. On the basis of the morphological characteristics and phylogenetic analyses of internal transcribed spacer rDNA, the causal agent was identified as Plasmodiophora brassicae. To our knowledge, this is the first report on the occurrence of P. brassicae on kohlrabi in Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.6
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• pp.745-750
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• 2014

This study investigated the effects of squid Todarodes pacificus liver oil on the serum lipids and adipose tissue weight of rats. The rats in the soybean oil (SO) group received a basic diet prepared according to the recommendations of the American Institute of Nutrition (AIN-93G), with 7% SO as lipid source. The rats in the Patagonian toothfish Dissostichus eleginoides muscle oil (PTFO) group received 5% PTFO and 2% SO as the lipid source, while the rats in the eco-friendly squid liver oil (EFSO) group received 5% EFSO and 2% SO. EFSO was prepared according to the method outlined in the author's patent. PTFO was extracted from muscle using a physical method in the author's laboratory. The prominent polyunsaturated fatty acids in the dietary oils were 18:2n-6 (54.3%) and 18:3n-3 (5.64%) in SO, DHA (6.77%) and EPA (3.61%) in PTFO, and DHA (26.2%) and EPA (9.94%) in EFSO. After feeding for 4 weeks, the serum lipid levels (e.g., triglyceride, total cholesterol, and low-density lipoprotein cholesterol) of the rats in the EFSO group were significantly reduced as compared with those in the SO group (P<0.05); those of the rats in the PTFO group were also reduced, albeit not significantly, compared with the SO group. On the other hand, the total white adipose tissue (visceral, epididymal, and perirenal) weight was significantly reduced in the EFSO and PTFO groups compared to the SO group. These results demonstrate that EFSO is an effective lipid modifying agent in rat blood, and that EFSO and PTFO have greater anti-obesity effects than SO.

• Textile Coloration and Finishing
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• v.35 no.4
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• pp.196-205
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• 2023

Water-dispersed pigment is on-going study for without air pollution in the textile and print industry. Primer treatment is essential for the substrate to improve the printing quality of eco-friendly water-dispersed pigment ink. Otherwise in the case of untreated primer, the water-dispersed pigment ink will dry onto the surface and cause defective images. This study was conducted on film substrate coating (primer) to fix eco-friendly water-dispersed pigment ink on film substrate. The drying, bleeding, and color strength of the pigment ink were examined depending on the composition and mixing ratio of the coating solution. The mixing ratio of silica gel in the coating film is increased to 0, 0.5, 1, 2 and 3 and results that DK-1-3 of silica gel ratio of 1 showed the lowest bleeding such as 52%, the letter thickness of 0.76mm and DK-1-5 of SG ratio of 3 showed the highest bleeding such as 304%, the letter thickness of 2.02mm. The mixing ratio of SPA in the coating film is increased to 2.5, 5, 7.5, SPA ratio of 7.5 has a bleeding ratio of 9% and letter thickness of 0.544mm. It showed the closest value to 0.5mm. According to the result, the optimal mixing ratio of binder, polymer coagulant, silica gel is 100:7.5:1.

• Fashion & Textile Research Journal
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• v.24 no.2
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• pp.260-266
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• 2022

Cellulose fiber is a material used in various fields. It is the most used type of fiber because of its excellent hygroscopicity and dyeability. Recently, as natural fiber materials have been highlighted due to the influence of eco-friendliness and well-being, bamboo fiber has become a commonly used eco-friendly fiber. Cellulose fibers are part of the -OH hydroxyl group, which means they are more chemically reactive than synthetic fibers. In this study, the cationization properties of bamboo-cotton blended fabrics cationized using CHPTAC (3-chloro-2-hydroxypropyl trimethyl ammonium chloride) in the PDC (padding-drying-curing) method were investigated. Various characteristics according to cationization were studied through elemental analysis, FT-IR (fourier-transform infrared spectroscopy) analysis, X-ray diffraction analysis, TGA (thermogravimetric) analysis, and SEM (scanning electron microscope) analysis. The nitrogen content of the cationized bamboo-cotton blended fabric increased with an increase in the concentration of the cationizing agent CHPTAC, and it was seen to be highly bound to cellulose molecules. As a result of the FT-IR analysis, both 100% pure cotton fabrics and CHPTAC-0 and CHPTAC-150 fabrics were seen to be typical cellulose. As a result of the X-ray diffraction analysis, both 100% pure cotton fabrics and CHPTAC-0 and CHPTAC-150 fabrics showed typical cellulose I structures. As a result of the X-ray diffraction analysis, both 100% pure cotton fabrics and CHPTAC-0 and CHPTAC-150 fabrics showed typical cellulose I structures. As the cationization progressed, micropores appeared on the surface of the blended fabric.

• Journal of the Korea Convergence Society
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• v.11 no.10
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• pp.213-217
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• 2020

An eco-friendly water purifier was developed using natural minerals, plants, and sludge from water purification plants. A wastewater complex treatment system using this water purification agent was developed. The wastewater complex treatment system goes through the process of inflow of contaminated water, input of water purification agent, operation of a pressurized flotation device, sludge flotation, sludge collection and treatment water discharge. This device was applied to the removal of green algae in livestock desorption liquid, broiler washing water, factory wastewater, sewage treatment plant and pond to obtain excellent removal rate. The use of natural water purification agents for organic waste purification has not been investigated.