• 한국식품저장유통학회지
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• 제25권1호
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• pp.79-89
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• 2018

본 연구에서는 율피 추출물을 이용하여 화장품 소재로서의 기능성을 조사하고자 효소종류별 및 가압추출 시간별에 따른 항산화 활성과 피부 미백 및 주름개선 효과를 실시하였다. 효소 종류별 및 가압추출 시간에 따른 율피 추출물의 추출수율은 12.42-29.80%로, C30m 추출물이 29.80%로 가장 높게 나타났다. 이화학적 특성으로 총 폴리페놀, 총 플라보노이드 및 총 탄닌 함량은 모두 C30m 추출물($1,000{\mu}g/mL$)에서 각각 22.69 g/100 g, 12.13 g/100 g 및 21.66 g/100 g으로 높은 함량을 나타내었으며, 총 당 함량은 H120m 추출물($1,000{\mu}g/mL$)에서 61.07 g/100 g으로 높은 함량을 나타내었다. 항산화 활성으로 DPPH radical 소거활성, ABTS radical 소거활성, superoxide radical 소거활성 및 FRAP 활성 모두 C30m 추출물($1,000{\mu}g/mL$)에서 각각 89.20%, 81.96%, 67.63% 및 $1,324.79{\mu}M$로 높은 항산화 활성을 나타내었으며, 모든 효소 처리구간에서 가압추출 시간이 증가함에 따라 항산화 활성이 감소하였다. 피부 미백 및 주름개선 효과를 확인하기 위해 tyrosinase 및 elastase 저해활성을 측정한 결과 C30m 추출물($1,000{\mu}g/mL$)에서 각각 61.32% 및 61.06%로 높은 저해활성을 나타내었으며, HE 추출물에서 가장 낮은 저해활성을 나타내었다. 이는 효소처리 및 가압추출에 의해 율피의 생리활성물질이 많이 용출된 것으로 판단되며, 율피의 새로운 추출공정 확립을 통해 항산화, 피부 미백 및 주름개선에 효과가 있는 항노화 기능성 소재로 화장품 제조용 원료 로 적합함을 확인하였다.

• 상하수도학회지
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• 제28권4호
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• pp.431-440
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• 2014

The ozonation process has been widely used for drinking water disinfection around the world. Recently, the pressurized ozone contactor, in which the side stream typed ozone injection method is installed, has been applied to water treatment system. In this study, numerical calculations were conducted to compare prototype and screw-type ozone contactors based on hydraulic effectiveness in more details. The prototype ozone contactor was already installed and operated in domestic water treatment plant, and the screw-type is the suggested one for improving ozone contact efficiency installing the screw plate to the prototype. Screw turn numbers of screw plate were changed as 3, 5, 7 and 9, respectively for numerical simulation. The CT(concentration of disinfectant in mg/L times time in minutes) value was considered as one of the options for evaluating disinfection ability. From the results, it could be concluded that the performance of the screw-type is higher than that of the protype contactor by controlling the variable T as the tracer time. Also, Morill index of the screw-type(turn numbers = 5 ) appeared to be lower than the other.

• 한국대기환경학회지
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• 제20권4호
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• pp.493-501
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• 2004

The principle of vortex tube and cyclone was introduced to enhance the treatment efficiency of waste air streams containing particulate matters, toluene, and others developed by Hangreen Tech, Ltd. and Hoseo Chemical and Industrial Technology R＆D Center. Adsorption, condensation, and/or coagulation could be induced at low temperature zone formed by vortex tube and Joule-Thomson expansion. The pressurized air was introduced at the tangential direction into the cyclone system applied with the coaxial funnel tube. Easily condensible vapors such as toluene. carbon dioxide, and water vapor were adsorbed enforcedly on coagulated or condensed materials which were formed as cores for coagulation or condensation by themselves. These types of coagulation or condensation rates were rapidly promoted as the diameter being growing up. The maximum removal efficiency for carbon dioxide and toluene was achieved to about 87 and 90 percent, respectively. The Joule-Thomson coefficients were increased with the pressure of air injected in the range of the relative humidities between 10% and 30%. An optimum value was observed within the range of the tested temperatures at a fixed pressure. In conclusion. it could be identified that the treatment efficiency would be depended on the pressure of the process air introduced and physical and chemical characteristics of waste air streams containing target materials for a designed system. The final design parameters should be decided depending upon the given system and target materials.

• 한국환경과학회지
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• 제16권6호
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• pp.699-706
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• 2007

Many lakes or irrigative reservoirs in Korea are rapidly contaminated due to the ever increasing pollutants. Although lots of treatment processes have been recommended and practiced, economical and technical improvement is currently needed. In this study, contaminated irrigation reservoir was treated using the proposed process which is consisted of fine air bubbles, coagulation and flotation. Fine bubbles, approximate diameter of 3 to $10{\mu}m$, were generated using cavitation in the pressurized tank and polyaluminum chloride was used as coagulants. This fine bubbles, coagulation and flotation effectively controlled the low density algae, for example, Chlorophyll-a was removed more than 97 %. Removal efficiency of COD, SS, T-N and T-P were 80.7%, 94.3%, 64.1 % and 92.4%, respectively. Pollutants released from the sediments was removed more than 80% of organics and 60-70 % of nutrients. Consequently, fine bubbles coagulation and flotation process could be effectively used as an alternative treatment method for the purpose of control of lake water quality.

• 한국식품과학회지
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• 제28권3호
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• pp.593-599
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• 1996

고압처리에 의한 효소반응의 조절을 연구하기 위하여 마늘에 압을 적용하여 alliinase의 압력에 의한 활성변화를 해석하였다. 마늘을 $25^{\circ}C$에서 10분간 고압 처리한 결과 alliinase 활성은 150 MPa 및 300 MPa에서 변화가 없었고, 500MPa에서는 완전히 불활성화되었다. 한편 정제된 alliinase는 150MPa에서 30%, 300 MPa에서 80%, 500MPa에서 100% 불활성화되어, 효소의 상태에 따라 압력에 의한 불활성화 정도가 다르게 나타나는 것을 알 수 있었다. 또한 고압처리에 의한 alliinase의 불활성화는 상온보다는 고온 또는 저온에서 효과적인 것으로 나타났다. $50^{\circ}C$에서 500MPa로 고압처리한 마늘은 allicin이 거의 생성되지 않아 매운 맛을 느낄 수 없었고, 휘발성 화합물의 50%이상이 제거되어, 마늘의 무취화에 고압처리를 적용할 수 있음을 확인하였다.

• Journal of Chest Surgery
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• 제36권6호
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• pp.431-435
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• 2003

개심술 후 발생하는 심부 흉골 창상감염(급성 종격동염)은 아주 심각한 합병증으로 높은 이환율, 사망률, 그리고 입원기간의 연장을 보인다 치료 결과는 주로 흉골 창상감염의 조기 진단과 적절한 외과적 조치에 의존한다. 개심술 후 심부 흉골 창상감염을 보였던 4예에서 광범위한 변연절제술, 항생제 용액의 높은 압력 하 세척, Robicsek방식에 의한 흉골의 재 고정, 항생제 용액을 사용한 세척-흡입법을 통해 성공적인 치료를 하였기에 문헌 고찰과 함께 보고한다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 추계학술대회 논문집
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• pp.617-620
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• 1997

In this paper, the thermal stress analysis of spent nuclear fuel disposal canister in a deep repository at 500m underground is done for the underground pressure variation. Since the nuclear fuel disposal usually emits much heat and radiation, its careful treatment is required. And so a long term safe repository at a deep bedrock is used. Under this situation, the canister experiences some mechanical external loads such as hydrostatic pressure of underground water, swelling pressure of bentonite buffer, and the thermal load due to the heat generation of spent nuclear fuel in the basket etc.. Hence, the canister should be designed to designed to withstand these loads. In this paper, the thermal stress analysis is done using the finite element analysis code, NISA.

• 펄프종이기술
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• 제34권2호
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• pp.67-72
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• 2002

The two stage laccase-assisted delignification process led to significant lignin removal in the non-pressurized treatments. It is clearly shown that an alkaline extraction prior to the second laccase treatment significantly increased the overall delignification by ∼15%. This is in line with the contention that the residual lignin has undergone structural changes during the alkaline extraction, and the resulting modified structures are susceptible to the laccase oxidation. In phenolic hydroxyl group, the pre- methylated sample was very responsive to the delignification process. The phenolic hydroxyl groups could be increased during side chain cleavage catalyzed by laccase. This finding demonstrates that the delignification oi etherified structures is an important reaction in the delignificaton by laccase.

• Journal of Welding and Joining
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• 제17권4호
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• pp.46-52
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• 1999

Some of the pressurized reactor pressure vessels used in many chemical plants are made of low alloy carbon steel plates internally clad with an austenitic stainless steel for improved anti-corrosion properties. In this study, metallurgic structure of the weld interface of A 387 Grade12Class1 low alloy carbon steel claded with A182-F321 austenitic stainless steel after thermal exposure simulation heat treatment was investigated to display a characteristic behavior of dissimilar metal weld interface with thermal exposure during service at high temperature and pressure. EPMA, STEM, vickers-hardness test were performed and the results were correlated with the microstructure. To estimate the depth of the carburized/decarburized bands quantitatively, a model for carbon diffusion was proposed. The validity of the proposed theoretical relationships was confirmed by the directly measured data from the welded parts failed during service.

• 상하수도학회지
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• 제22권6호
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• pp.689-696
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• 2008

In a water treatment process a complete and homogeneous dispersion of the coagulants in the raw water could be most important factor. This research was performed to evaluate coagulation performance of the in-line-orifice mixer which was recently introduced as a rapid mixing device. The test was to determine the actual coagulant dispersion distribution on the overall cross-section at a distance of 1.6~3D from the chemical injection point by measuring zeta potential. From the results of zeta potential test, it was shown that the coagulant dispersion within the in-line orifice mixer was occurred very unevenly. The results have confirmed that it is necessary to increase the velocity of coagulants injection or pressurized water rates, in order to reduce nonuniform distribution of chemicals.