• Clean Technology
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• v.26 no.4
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• pp.311-320
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• 2020

In this study, the photocatalytic degradation of rhodamine B (RhB), methyl orange (MO) and methylene blue (MB) was carried out under visible light irradiation using CdS and CdZnS/ZnO photocatalysts prepared by a simple precipitation method. This study focused on examining the effect of physicochemical properties of dye and photocatalyst on the reaction pathway of photocatalytic degradation. The prepared photocatalysts were characterized by XRD, UV-vis DRS and XPS. Both the CdS and CdZnS/ZnO photocatalysts exhibit an excellent absorption in the visible light and the UV light regions. It was observed that the photocatalytic degradation of MO proceeds via the same reaction mechanism on both the CdS and CdZnS/ZnO photocatalysts. However, the photocatalytic degradation of RhB and MB was found to proceed through a different reaction pathway on the CdS and CdZnS/ZnO catalysts. It is interesting to note that MB dimer was formed on the CdS catalyst at the beginning of the photocatalytic reaction, while the MB monomer was degraded during the overall photocatalytic reaction on CdZnS/ZnO. The above results may be mainly ascribed to the difference of band edge potential of the conduction band in the CdS and CdZnS/ZnO semiconductors and the adsorption property of dye on the catalysts.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.3
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• pp.235-244
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• 2022

In this study, the cell viability, radical scavenging ability, elastase activity, moisturizing activity, and antimicrobial activity of mixed fermented extract of vitamin tree fruit, acai palm fruit, mango, lemon, apricot and blueberry as an active ingredient were measured. The experiment was performed at three concentrations(0.5 / 1.5 / 2%), since cytotoxicity was not shown at these three concentrations. Based on this, a radical scavenging experiment was conducted to compare with L-ascorbic acid, a representative raw material of an antioxidant material. The results showed that the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability was 95.1 ± 0.6%, 94.3 ± 0.7%, 95.3 ± 0.6%, 95.1 ± 0.7%, 95.1 ± 0.3%, 95.5 ± 0.3%, and 95.4 ± 0.4% respectively, when the concentration of the mixed fermentation extract was 2%. As the concentration increased at the three concentrations (0.5/1.5/2%) and the content of blueberry extracts increased, sample 7 showed excellent elastase activity at a concentration of 2% to 0.9 cm, such as retinol crystal, and moisturizing activity was also found to be 71.5%, 75.6%, and 81.6%, respectively. Particularly, at the 2% concentration of the mixed fermented extract, the antibacterial activity effect on Propionibacterium was very excellent in sample 7. Therefore, it is considered that it is worth developing the mixed fermented extracts of 2% concentration as a cosmetic component with antioxidant, moisturizing, and antibacterial properties.

• Journal of the Korean Applied Science and Technology
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• v.39 no.1
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• pp.34-41
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• 2022

As the use of chemical products increases in daily life, the removal of dye waste has also emerged as an important environmental issue. This dye waste can be decomposed using a photocatalyst, and the photocatalyst can be synthesized very cost-effectively by using the sol-gel technology. The sol-gel technology is not only very useful for nanoscale film formation, but also can simply form multilayer structures. Using a multiple spin coating method, in this study, a ZnO film with a multilayered structure (3 layers, 5 layers) was formed by using zinc oxide (ZnO), which is effective in decomposing various dyes. For performance comparison, a ZnO film having a single layer structure by a single spin coating method was prepared as a control. Structural and elemental analysis of ZnO film was performed using an X-ray diffraction analyzer and an energy dispersive X-ray spectrometer. A nanowire-like surface morphology could be observed through a scanning electron microscope. Additionally, UV-Vis spectrophotometer was used to measure the absorbance of UV light. The ZnO film with a five-layer structure degraded the simulated methylene blue by 49% more than the ZnO film with a single-layer structure. In conclusion, it was found that ZnO having a multilayered structure is useful as a photocatalyst that decomposes methylene blue dye more effectively.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.49 no.2
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• pp.159-167
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• 2023

Titanium dioxide (TiO₂) is commonly used in sunscreen formulations to protect the skin surface and prevent the penetration of harmful ultraviolet (UV) rays by the physical scattering action of light. However, a disadvantage of using TiO₂ is that it can cause white turbidity when used on skin due to its inactive mineral ingredient. In addition, when TiO₂ particles are reduced to nanosize to eliminate opacity, they can increase the transmittance of visible light and reduce whitening, but may lead to serious skin problems, such as allergic inflammation. To overcome these issues, the bandgap of TiO₂ was controlled by adjusting the amount of oxygen defect and nitrogen amount, resulting in color TiO₂ tailored to the skin. This innovative technology can reduce the whitening phenomenon and effectively block blue light, which is known to cause skin aging by inducing active oxygen. The bandgap controlled TiO₂ compounds proposed in this study are hypoallergenic, broad-spectrum, and environmentally friendly. Furthermore, these compounds have been shown to significantly enhance sun protection factor (SPF) of sunscreens, demonstrating their compatibility with blue light blocking products.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.49 no.2
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• pp.183-192
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• 2023

In this study, we investigated the antioxidant activity, anti-inflammatory activity, whitening, moisturizing, wound-healing, cell proliferation and cell protective effects of 70% EtOH and hot water extract from Scutellaria baicalensis. For the anti-oxidative test, the 70% EtOH and hot water extract showed DPPH radical scavenging activities. In the anti-inflammatory tests, 70% EtOH and hot water extract inhibited the production of NO, pro-inflammatory cytokine (IL-6) and prostaglandin (PGE₂). In addition, it was confirmed that the 70% EtOH and hot water extract inhibited the melanin production, and increased production of hyaluronic acid (HA), a moisturizing factor. As a result of cell migration and proliferation assay, 70% EtOH extract promoted the cell growth in HaCaT cell. Additionally, 70% EtOH and hot water extract showed cell protective effects against UVB, and 70% EtOH extract also showed cell protective effects agianst blue light. Based on these results, it is concluded that the 70% EtOH and hot water extract from Scutellaria baicalensis could be potentially applicable as anti-oxdiative, anti-inflammation, whitening, moisturizing, wound-healing, cell proliferation and cell protective effects in cosmetic natural materials.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.859-860
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• 2012

• 농업기술회보
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• v.48 no.5
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• pp.18-18
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• 2011

요즘 국내 농산물 산업에서의 화두는 안전성과 기능성이 결합된 친환경농산물 생산에 맞춰져 있다. 이와 함께 농업과학기술 분야에서는 내실 있는 친환경농업을 실천하기 위해 재배기술 및 화학농자재를 대체할 소재개발 연구가 활발히 진행되고 있다.

• 정보화사회
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• s.174
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• pp.42-45
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• 2005

블루투스는 출발 당시 가정 혹은 사무실에서 자주 사용하는 PC.프린터.PDA와 같은 정보기기, TV.냉장고 등 가전제품의 복잡한 선을 말끔히 없앨 수 있는 근거기 무선 통신의 대표 주자로 주목을 받았다. 하지만 무선랜.적외선 통신 등 다른 무선 기술과의 공존 문제, 호환 등의 기술적 장벽으로 상용화에 큰 어려움을 겪어왔다. 최근 블루투스 기술은 이러한 문제를 하나씩 해결하며 무선 통신의 강자로 화려하게 부활하고 있다.

• 한국상하수도협회지
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• s.24
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• pp.44-45
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• 2008

세계인의 평균수명 증가에는 의료기술의 발달이 큰 몫을 했다. 하지만 수도시설의 보급 역시 적지 않은 영향을 미쳤다고 볼 수 있다. '블루 골드(Blue Gold)' 시대를 맞아 각국의 수돗물 서비스의 수준이 곧 국가경쟁력으로 이어지고 있는 시점에서 수도산업을 공고히 하기 위한 국가 차원의 노력이 필요한 때이다.

• Venture DIGEST
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• s.86
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• pp.26-26
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• 2005

예비창업자에게는 실질적인 도움을 주고 개인적으로는 영업인맥도 맺자.’이 윈윈전략은 이미 레드마켓인 인터넷쇼핑몰에서 뜻밖의 블루마켓을 일구어내는 초석이 되었다. 온라인쇼핑몰 상품분배 시스템을 개발한 굿스뱅크코리아(대표 김장관)의 상부상조 창업 이야기를 들어본다.