• Membrane Journal
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• v.25 no.2
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• pp.85-98
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• 2015

A global trend of replacing metal or glass containers with polymer-based packaging materials has been prevalent in the food packaging industry due to their ease in processibility, excellent transparency, and good cost efficiency. Barrier polymers tend to show low permeabilities for atmospheric gases such as oxygen, carbon dioxide, and water vapor, which allow them to be utilized in the food and beverage packaging industry. With the current global trend, expansion of polymeric packaging materials to new markets such as oxygen sensitive juices, flavored water, and energy drinks requires improved $CO_2$ and $O_2$ barrier properties. The improvement of the existing polymer-based barrier platform will enable a rapid market impact. In this paper, the current barrier technologies such as (1) antiplasticization-induced barrier materials, (2) synergistic effect of antiplasticization and crystallization, (3) new barrier polymers, (4) nanocomposite materials, and (5) polymer blending are introduced with their characterization techniques for the development of advanced packaging materials.

• Journal of the Korean Society for Nondestructive Testing
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• v.36 no.1
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• pp.60-67
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• 2016

A pressurized heavy water reactor (PHWR) designed to refuel in service produces the energy required by nuclear fission. The fuel channel consists of components such as a pressure tube which directly contacts the fuel and is a passage for the reactor coolant, a calandria tube which contacts the moderator and is rolled joint with calandria, and a spacer which is not to contact the pressure tube and a calandria tube. As the fuel channel is one of the most important equipments, it requires accurate and periodic inspections to assess the integrity of a reactor in accordance with CSA N285.4. A fuel channel inspection system is developed to inspect fuel channels during in-service inspection in Wolsong unit. In this paper, the results and considerations of a field test are presented in order to show the effectiveness of the developed fuel channel inspection system.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.11a
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• pp.31-31
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• 2011

섬유제품은 대부분은 흡수성 또는 흡유성을 가지고 있어 물이나 기름이 등을 쉽게 흡수하는 성질이 있다. 이러한 성질 때문에 물이나 기름 등의 접촉에 의한 얼룩과 오염이 잘 되는 단점을 가지고 있다. 이러한 문제점을 해소하기 위하여 원단에 대한 발수, 발유, 방오가공 등이 연구되어 왔으며 섬유의 고유한 화학적, 기계적 물성을 유지하면서 표면과 이면이 다른 특성을 가지도록 유도하여 기능성을 부여하는 편면가공을 주목을 받게 되었다. 본 연구에서는 불소계로 발수처리 된 PET직물에 저온 Plasma와 Sputter을 이용하여 직물의 한쪽 면에는 친수성과 다른 면에는 발수성이 동시에 나타나는 편발수에 관한 실험을 했다. 불소계로 발수처리 된 시료와 저온 Plasma처리된 시료와 Sputter처리된 시료(처리면, 미처리면)를 접촉각 5회 측정하여 평균값을 나타냈다. 발수처리 된 시료의 평균 접촉각 값은 $149^{\circ}$이며, 저온 Plasma의 평균값은 $45^{\circ}$(처리면) $128^{\circ}$(미처리면), Sputter는 $74^{\circ}$(처리면) $144^{\circ}$(미처리면) 으로 가공처리 된 시료에는 양면의 접촉각이 확연한 차이가 나타난 걸로 미루어 보아 편면발수효과가 얻어졌다고 판단된다. SEM 측정을 통하여 관찰한 경우, 발수처리 된 시료에서는 불소계 발수제의 흔적이 보였다. 저온 Plasma, Sputter 처리된 시료에서는 처리시간이 높아짐에 따라서 시료표면에 코팅된 불소계 발수제 막들이 점점 파괴되는 것을 관찰할 수 있었다. 그리고 건식가공으로 인하여 처리된 표면에는 Etching작용이 일어나 표면적이 넓어져 친수화가 일어난 것으로 생각된다. 이처럼 저온 Plasma가공과 Sputter가공으로 편발수를 얻을 수 있다면 에너지 절약, 처리공정과 시간단축 등 여러 가지 장점이 기대된다.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.367-367
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• 2022

토지이용의 고도화에 따라 비점오염원 부하는 증가하는 추세이며 기후변화에 따른 강우강도 증가 등으로 지표면에 축적된 고농도의 비점오염물질이 하천으로 유출, 수질오염을 가중시키고 있어 비점오염원 관리가 필요하다. LID 기법은 자연적 기작(mechanisms)과 공정(process)을 이용하여 생태계의 물질순환(물순환 포함)과 에너지 흐름이 원활하도록 조성하는 기법으로, 불투수층면에서 발생되는 강우유출수를 관리 가능하다. LID 시설에는 전처리 시설을 두어 초기 고농도의 입자상 물질을 저감시키고, 강우유출수 저류공간을 통한 유출저감, 첨두유량 등을 저감시킨다. 이러한 전처리 시설에는 유기물질 및 영양소의 생물학적 제거를 위한 미생물 서식공간의 제공 등의 역할을 수행하기 위하여 다양한 여재를 적용하고 있다. 본 연구는 비점오염물질 유입이 LID 기법 전처리 시설 내 여재층의 물리·화학적 및 생물학적 환경을 평가하였다. 3개 시설 모두 100%의 불투수층에서 발생되는 강우유출수를 처리하는 LID 시설을 연구대상으로 선정하였으며, 각각의 전처리 시설에는 자갈, 우드칩, 쇄석 등이 적용되어 있다. 퇴적물의 경우 가장 상부에 존재하는 층으로 퇴적물의 오염물질 농도는 2~10.7배 이상 매우 높게 나타났다. 우드칩의 경우 다른 여재에 비해 높은 함수량과 유기물 함량을 보였으며 이는 우드칩의 수분을 보유하는 능력과 거친 표면공극에 오염물질이 부착되기 때문으로 나타났다. 또한, 같은 무기성 여재인 쇄석과 자갈의 경우 여재 크기의 차이를 보임에도 불구하고 미생물의 군집구성과 함수량의 차이를 보이는 것으로 평가되었다. 유기물의 함량이 낮은 강우유출수의 생물학적 처리능력을 향상시키기 위해서는 유기성 여재가 필요하며, 다공성 무기 멀칭재를 적용하고 하부의 토양은 적정 유기물을 배합하여 질산화 및 탈질화 유도가 가능하도록 설계가 필요한 것으로 분석되었다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.10
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• pp.424-429
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• 2018

In this study, an expansion joint that is susceptible to waterhammer was tested for its vibration durability. The operation data for the hydraulic actuator was the expansion length of the expansion joint when the waterhammer occurred. In the case of the vibration durability test, the internal temperature status of the expansion joint was assumed to be a stress factor and a lifespan prediction model was assumed to follow the Arrhenius model. A test was carried out by increasing the internal temperature status at $30^{\circ}C$, $50^{\circ}C$, and $65^{\circ}C$. By a linear transformation of the lifespan data for each temperature, a constant value and activation energy coefficient was induced for the Arrhenius equation and verified by comparing the value of a lifetime prediction model with the experimental value at $85^{\circ}C$. The failure modes of the ongoing or finished test were leakage, bellows separation, and internal deformation. In the future, a composite lifespan prediction model, including two more stress factors, will be developed.

• The Journal of the Convergence on Culture Technology
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• v.5 no.1
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• pp.413-416
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• 2019

Alstroemeria (Alstroemeriaceae) is one of the most important cut flowers in international market. Especially, characteristics like long vase-life, various colors, tolerance to low temperature and a low energy requirement during cultivation have stimulated this success. Because of its characteristics such as low multiplication rates, time-consuming process and high risk of carrying viral disease, in vitro propagation techniques based on rhizome meristems culture have been developing nowadays. The callus induction has various cultivation sites compared with the direct plant generation method, and if the callus is maintained well, the plant differentiation can be performed simultaneously while maintaining the callus, so that it can be used for mass proliferation. In this study, we tested various hormones and cultivars for efficient callus induction. As a result of culturing between the nodes and the internodes, the callus began to be formed after 8 weeks, and the calli incidence in the nodes was higher than that between the internodes. Also, in the comparison of 2,4-D and picloram, the callus incidence rate was up to 2 times higher in the medium treated with 2,4-D. Using these results, it is thought that it will help establish the system of mass propagation system of Alstroemeria and cultivate new varieties.

• Korean Chemical Engineering Research
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• v.54 no.5
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• pp.687-692
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• 2016

Biomass has been concerned as one of the alternative energy resources because it is renewable, abundant worldwide, eco-friendly, and carbon neutral. Quercus variabilis has been studied to understand pyrolysis reaction characteristics, and to evaluate the efficiency of bio-energy production from fast pyrolysis. Quercus variabilis were fast pyrolyzed in a bubbling fluidized bed reactor at various reaction conditions. The effects of pyrolysis temperature between $400^{\circ}C$ and $550^{\circ}C$ on product yields were investigated. The yield of bio-oil was changed between 36.98 wt% and 39.14 wt%, and those of gas yield was 33.40 and 36.96 wt% with increasing reaction temperature. The higher heating value (HHV) of bio-oil at $500^{\circ}C$ ($3.0{\times}U_{mf}$) was 20.18 MJ/kg. The gas compositions were similar for all reaction conditions such as CO, $CO_2$ and $CH_4$, and $CO_2$ selectivity was the highest (37.16~50.94 mol%). The bio-oil has high selectivities for furfural, phenol and their derivatives such as 1-hydroxy-2-propanone, 2-methoxy-phenol, 1,2-benzendiol, 2,6-dimethoxy-phenol.

• Journal of Animal Science and Technology
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• v.46 no.5
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• pp.763-772
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• 2004

The patterns of fungal growth and fiber digestion under the microscope, and tile productions of fibrolytic enzyme were studied in an in vitro culture with Neocallimastix frontalis SA when either filter paper or rice straw was provided as sole energy source. Under the microscopic observation, active zoospores attachment, sporangium development and complex rhizoidal system were founded on the surface and at the edge of filter paper. After 7 days of incubation, a reduced fiber mass, a decreased fiber cohesion and a weakened fiber structure by fungal digestion were clearly observed. Similar fungal development was observed with rice straw, but fungal growth and digestion took place mostly on the damaged and exposed portion of rice straw. Although there were some differences in absolute concentration and pattern, the concentration of both cellulase and xylanase increased with incubation time with the higher activity being obtained with filter paper. Their differences were large especially after 48 and 96hr of incubation(P< 0.05). The filter paper was more good inducer of cellulolytic and xylanolytic enzymes compared with complex substrate, rice straw. These findings suggest that the filter paper is the better energy source for N frontalis than the complex substrate, and structural disintegration by physical process is able to help rumen fungal growth on the lignified roughage although anaerobic rumen fungi have mechanical and enzymatic functions for fiber digestion.

• Journal of Nutrition and Health
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• v.48 no.4
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• pp.299-309
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• 2015

Purpose: The purpose of this study was to examine the effect of black soybean (CJ-3) testa extracts on lipid profiles in streptozotocin (STZ)-induced diabetic rats. Methods: One control group and four STZ-induced diabetic groups with different doses of black soybean (CJ-3) testa extracts treatment [0 mg/kg (diabetic control, EX), 250 mg/kg (EX-250), 500 mg/kg (EX-500), 1,000 mg/kg (EX-1000)] were orally administered for 4 weeks. Results: All CJ-3 treatment groups had remarkably lower serum triglyceride (TG) levels than that of EX group (p < 0.05) whereas hepatic TG contents did not show any differences. Results from serum total cholesterol (TC) concentrations of EX-250 and EX-1000 groups were decreased compared to EX group (p < 0.05). Furthermore, protein levels of 3-hydroxy-3-methyl-glutaryl-Coenzyme A (HMG-CoA) reductase from the liver decreased in all treatment groups (p < 0.05). However, significant differences were not observed in serum glucose and insulin, and glucose transporter 4 (GLUT-4) protein expression in skeletal muscle tissue. Conclusion: These results suggest that black soybean testa extracts could be useful for improvement of hyperlipidemia and hypercholesteremia in diabetes.

• The Korean Journal of Pesticide Science
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• v.2 no.3
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• pp.64-69
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• 1998

New thirty derivatives of 5,6-dihydro-2-trifluoromethyl-1,4-oxathiin carboxanilide as substrate(S) were synthesized and their fungicidal activities in vivo against rice sheath blight(Rhizoctonia solani) and wheat leaf rust(Puccinia recondita) were examined. The structure activity relationships(SAR) between the activities($pI_{50}$) and a physicochemical parameters of substituents(X) at the phenylcarbamoyl group were analyzed using the adaptive regression analysis method. The 3-methoxy, 11, 3-isopropyloxy, 13 and 3-isopropyl substituent, 25 as X on the phenylcarbamoyl group exhibited the most highest fungicidal activity against the two fungi. The fungicidal potency of the (S) against Puccinia recondita was higher than Rhizoctonia solani. In case of Rhizoctonia solani, the molecular hydrophobicity(${\pi}>0$) and resonance effect(R<0) by meta-alkyl substitutents with electron donating were important factors in determining fungicidal activity. And the HOMO energy(HOMO>0), ABSQ, sum of absolute values of the atomic charges on each atom and specific polarizability(Sp.Pol<0) of (S) were significantly influential towards fungicidal activity against Puccinia recondita.. The interaction between (S) and receptor agonist from the based on SAR studies proceeds through charge-control reaction, and conditions to show higher activity has been also discussed.