• 한국표면공학회지
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• 제33권4호
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• pp.241-250
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• 2000

Popcorn cracking phenomena frequently occur in thin plastic packages during the solder reflow process, which are definitely affected by poor adhesion of Cu-based leadframe to epoxy molding compounds (EMCs). In the present work, in order to enhance the adhesion strength, a brown-oxide treatment on the Cu-based leadframe was carried out and the adhesion strength of leadframe/EMC interface was measured in terms of fracture toughness by using sandwiched double-cantilever beam (SDCB) specimens. After the adhesion tests, fracture surfaces were analyzed by SEM, AES, EDS and AFM to make the failure path clear. Results showed that failure path was closely related to the oxidation time and the interfacial fracture toughness.

• Journal of Ginseng Research
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• 제39권1호
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• pp.1-6
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• 2015

Abnormal changes in skin color induce significant cosmetic problems and affect quality of life. There are two groups of abnormal change in skin color; hyperpigmentation and hypopigmentation. Hyperpigmentation, darkening skin color by excessive pigmentation, is a major concern for Asian people with yellowe-brown skin. A variety of hypopigmenting agents have been used, but treating the hyperpigmented condition is still challenging and the results are often discouraging. Panax ginseng has been used traditionally in eastern Asia to treat various diseases, due to its immunomodulatory, neuroprotective, antioxidative, and antitumor activities. Recently, several reports have shown that extract, powder, or some constituents of ginseng could inhibit melanogenesis in vivo or in vitro. The underlying mechanisms of antimelanogenic properties in ginseng or its components include the direct inhibition of key enzymes of melanogenesis, inhibition of transcription factors or signaling pathways involved in melanogenesis, decreasing production of inducers of melanogenesis, and enhancing production of antimelanogenic factor. Although there still remain some controversial issues surrounding the antimelanogenic activity of ginseng, especially in its effect on production of proinflammatory cytokines and nitric oxide, these recent findings suggest that ginseng and its constituents might be potential candidates for novel skin whitening agents.

• 한국수산과학회지
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• 제48권2호
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• pp.151-157
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• 2015

This study was conducted to evaluate the effect of lactic acid bacterial fermentation on the antioxidant and anti-inflammatory activity of an edible brown alga, Eisenia bicyclis. Lactic acid bacteria were inoculated into and cultivated in E. bicyclis water extract. The antioxidant activity of the extract was assayed before and following fermentation. Antioxidant activity was determined by assaying the levels of radical scavenging activity against 2,2'-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radical and alkyl radical. The lactic acid bacterial fermentation of E. bicyclis extract resulted in enhanced antioxidant activity. The greatest enhancement of antioxidant activity was seen in the DPPH radical scavenging assay, in which E. bicyclis extract was fermented by Pediococcus pentosaceus MBP-34 strain for 12 h. This fermented extract also exhibited higher inhibitory activity (96.66%) on nitric oxide production compared with other lactic acid bacterial fermented extracts or raw extract (189.60%). In conclusion, fermentation by bacterial strain is an attractive strategy for developing value-added food ingredients.

• 한국자원식물학회지
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• 제24권3호
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• pp.298-303
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• 2011

A large number of edible seaweeds are consumed by the coastal peoples of Asia. Some of them are used in traditional remedies in many parts of the world. In this study we investigated effects of supplementation with ethyl acetate extracts of the brown alga Eisenia bicyclis (EBE) on rat macrophage to evaluate the possibilities as immune-modulators. Twelve male SD rats were divided into two groups and the treatments were as follows: A, no Eisenia bicyclis extract (EBE) intake and distilled water ; B, oral supplemented with EBE 200 mg/kg. After 5 weeks of supplementation, rats were sacrificed to assess the effect on peritoneal macrophage functions. We showed no increasing effects on tumoricidal activity, phagocytic activity and NO production in macrophages in EBE supplementation group. However, EBE supplementation suppressed NO-iNOS production and p65 translocation into the nucleus in LPS-stimulated macrophages. Overall, these results suggest that the supplementation of EBE might have an anti-inflammatory effects on NO-iNOS production in macrophages throughout the inhibition of NF-${\kappa}B$ activation.

• 한국세라믹학회지
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• 제13권2호
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• pp.24-30
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• 1976

To observe the influence of tetrahedral and octahedral preference of cations of Ni2+, Ti4+ upon the formation and the color development of the MgO-SnO2 spinel containing Ni2+ and Ti4+ ions, the gradual substitution of Ni2+ ions for Mg2+ ions and of Ti4+ ions for Sn4+ ions of the spinel in NiO-MgO-SnO2-TiO2 system was carried out. On samples prepared by calcining the oxide and basic carbonate mixtures at 130$0^{\circ}C$ for 1.5 hour, the X-ray analysis, measurement of reflectance and the test of their stability as a glaze pigment were also carried out. On samples prepared by calcining the oxide and basic carbonate mixtures at 130$0^{\circ}C$ for 1.5 hour, the X-ray analysis, measurement of reflectance and the test of their stabiality as a glaze pigment were also carried out. The results are summarized as follows. 1) As increasing the amounts of Ni2+ ions in the xNiO.(2-x)MgO.SnO2 system, spinel was not formed easily, and the mixed-spinel was formed in NiO.MgO.SnO2 of x=1 but the spinels was not formed completely in the range of x>1.5 2) The spinels was not more formed in NiO-MgO-TiO2 system than NiO-MgO-SnO2 system. Therefore, Ti4+ ions have strong octahedral preference than Sn4+ ions. The color changed the yellow region little. The mixed-spinel or non-spinel was formed easily NiO.TiO2, MgO.TiO2 of illmenite type as the gradual substitution of Ti4+ ions for Sn4+ ions. 3) The results of glaze test. The color changed from white through graish brown to brown as the gradual substitution of Ni2+ ions for Mg2+ ions in calcium-zinc glaze and calcium glaze, and from white through light yellowish beige to dull beige in tile glaze. Also, the color did not change generally as the gradual substitution of Ti4+ ions for Sn4+ ions in NiO-MgO-SnO2-TiO2 system.

• Nutrition Research and Practice
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• 제11권1호
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• pp.3-10
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• 2017

BACKGROUND/OBJECTIVES: Sargassum horneri is an edible brown alga that grows in the subtidal zone as an annual species along the coasts of South Korea, China, and Japan. Recently, an extreme amount of S. horneri moved into the coasts of Jeju Island from the east coast of China, which made huge economic and environmental loss to the Jeju Island. Thus, utilization of this biomass becomes a big issue with the local authorities. Therefore, the present study was performed to evaluate the anti-inflammatory potential of crude polysaccharides (CPs) extracted from S. horneri China strain in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. MATERIALS/METHODS: CPs were precipitated from S. horneri digests prepared by enzyme assistant extraction using four food-grade enzymes (AMG, Celluclast, Viscozyme, and Alcalase). The production levels of nitric oxide (NO) and pro-inflammatory cytokines, including tumor necrosis factor (TNF)-${\alpha}$ and interleukin (IL)-$1{\beta}$ were measured by Griess assay and enzyme-linked immunosorbent assay, respectively. The levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), nuclear factor (NF)-${\kappa}B$, and mitogen-activated protein kinases (MAPKs) were measured by using western blot. The IR spectrums of the CPs were recorded using a fourier transform infrared spectroscopy (FT-IR) spectrometer. RESULTS: The polysaccharides from the Celluclast enzyme digest (CCP) showed the highest inhibition of NO production in LPS-stimulated RAW 264.7 cells ($IC_{50}$ value: $95.7{\mu}g/mL$). Also, CCP dose-dependently down-regulated the protein expression levels of iNOS and COX-2 as well as the production of inflammatory cytokines, including TNF-${\alpha}$ and IL-$1{\beta}$, compared to the only LPS-treated cells. In addition, CCP inhibited the activation of NF-${\kappa}B$ p50 and p65 and the phosphorylation of MAPKs, including p38 and extracellular signal-regulated kinase, in LPS-stimulated RAW 264.7 cells. Furthermore, FT-IR analysis showed that the FT-IR spectrum of CCP is similar to that of commercial fucoidan. CONCLUSIONS: Our results suggest that CCP has anti-inflammatory activities and is a potential candidate for the formulation of a functional food ingredient or/and drug to treat inflammatory diseases.

• 청정기술
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• 제26권2호
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• pp.96-101
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• 2020

이 논문에서는 3세대 바이오매스 중 거대조류, 즉 해조류 바이오매스로부터 유래된 바이오가스를 연료로 사용하여 열, 전력 및 수소를 생산하는 삼중발전의 타당성 평가를 수행하였다. 이를 위해 3 MW급 고체산화물 연료전지와 가스터빈, 그리고 유기 랭킨 사이클로 이루어진 상용 규모의 열, 전력 및 수소 생산공정을 공정모사기를 사용하여 설계, 모사하였고, 공정모사로 부터 얻은 열 및 물질 수지를 통해 각 단위조작 장치의 가격을 추정하고 경제성을 분석하였다. 수소를 생산하기 위해 고체산화물 연료전지의 설계를 수정하였는데, 연료전지 내 애프터-버너를 제거하고 수성-가스 전환 반응기를 추가하였다. 공정모사 결과 설계된 삼중발전 공정은 시간당 3.47톤의 건조 갈조류 원료로부터 생산된 2톤의 바이오가스를 이용하여 2.3 MW의 전력과 50 kg hr^-1의 수소를 37%의 효율로 생산한다. 이 결과를 토대로 가장 현실적인 시나리오에 대해 경제적으로 평가하고 BESP (breakeven electricity selling price)를 계산하였는데, ¢10.45 kWh^-1로 기존의 고정 발전 대비 동등 이상의 수준으로 나타났다.

• 한국임상수의학회지
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• 제32권4호
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• pp.289-294
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• 2015

Fucoidan은 갈조류로부터 추출되는 황산다당류로 다양한 생리학적 활성을 갖고 있다. 본 연구의 목적은 LPS로 자극한 돼지 말초혈액 단핵구세포(PBMCs)의 NO 생산에 있어 fucoidan의 효과를 검토하고, 이러한 효과가 iNOS의 발현과 AP-1의 활성화와 관련이 있는지를 조사하는데 있다. LPS 무처치 돼지 PBMCs에서 fucoidand의 처리는 NO 생산과 AP-1활성에 대해 효과를 보이지 않았다. 또한 iNOS와 AP-1의 mRNA 발현도 fucoidan 처치에 의해 영향을 받지 않았다. 그러나 LPS로 자극한 PBMCs에서는 NO 생산과 AP-1의 활성 그리고 iNOS와 AP-1의 mRNA 발현이 현저하게 증가하였다. 이와 같은 LPS에 의한 돼지 PBMCs의 NO 생산과 AP-1 활성증가는 fucoidan 첨가에 의해 감소되었다. 또한 fucoidan은 LPS에 의한 iNOS와 AP-1의 mRNA 발현증가도 억제시켰다. 이상의 결과는 fucoidan이 LPS 자극 돼지 PBMCs에서 iNOS 발현과 AP-1 활성의 억제와 함께 NO 생산을 하향 조절함으로써 항염증효과를 나타내는 것으로 사료되었다.

• 청정기술
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• 제28권3호
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• pp.232-237
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• 2022

해조류 바이오매스 중 갈조류의 주요 구성 성분인 알긴산은 다양한 산업에서 널리 사용되어지며, 촉매적 저분자화를 통해 당, 당알코올, 퓨란계, 그리고 유기산과 같은 고부가가치 화합물로 전환할 수 있다. 본 연구에서는 루테늄 담지 활성탄과 마그네시아를 혼합하여 알긴산 저분자화 반응에 적용하고자 하였다. 이러한 불균일계 촉매 시스템은 생성물에 대한 분리가 용이하고 정제 과정의 간소화가 장점으로 작용한다. 반응 결과, 탄소 수 5개 이하의 저분자량 알코올 및 유기산이 생성되었으며, 최적의 반응 조건 탐색을 통해 최종적으로 1 wt% 알긴산 수용액 30 mL, 루테늄 담지 활성탄 100 mg, 마그네시아 100 mg, 반응 온도 210 ℃, 반응 시간 1 h의 반응 조건에서 29.8%의 알코올에 대한 탄소 수율과 43.8%의 알코올 포함 액상 생성물에 대한 총 탄소 수율을 확보하였다.

• 한국광물학회지
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• 제22권2호
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• pp.153-162
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• 2009

석간주는 적색과 적갈색 등 붉은 빛을 띠는 전통 광물성 안료로 주성분은 산화철이다. 석간주의 광물학적 특성과 기능성을 연구하기 위해서, 문헌에 옛 산지로 나와있는 울릉도 주토굴에서 석간주를 채취하였다. 울릉도주토굴의 석간주광석은 감람석현무암과 각섬석조면암 경계면에서 단속적으로 산출하며, 적갈색 또는 황갈색을 띠고 대체로 점토질이며 부분적으로 암편을 함유하고 있다. 석간주광석 중 적색은 적철석에 의한 것이며, 황갈색은 훼리하이드라이트에 의한 것이다. 울릉도석간주광석의 색상을 결정하는 산화철광물들은 고토양중에서 함철 수용액으로부터 훼리하이드라이트라는 광물로 침전되었으나 부분적으로 적철석으로 전이되었다. 석간주광석을 전통방식에 의해 안료로 제작하여 목재에 재현한 색상은 전통 건축물에서 측정한 붉은색 색상과 유사하였다. 울릉도석간주안료의 내습기능과 방염기능은 화학석간주안료에 비해 월등히 우수한 것으로 확인되었으며 연소시험에서 화학석간주안료는 발화와 연소를 촉진시키는 결과를 보였다. 울릉도석간주안료가 함유된 배지에서 목재부후균의 성장이 저지되는 경향을 보여 울릉도석간주는 방부성을 지닌 채색안료로 판단된다.