• 환경생물
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• 제35권4호
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• pp.595-603
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• 2017

The macroalgal community structure was examined at the subtidal zones of six study sites, on the Southern coast of Korea from between May and August 2015. A total of 132 seaweeds, comprising 10 green, 28 brown and 94 red Seaweed, were identified. The seaweed biomass was $80.32g\;dry\;wt.\;m^{-2}$ in average, and it was maximal at Geomundo ($166.94g\;dry\;wt.\;m^{-2}$) and minimal at Byeongpungdo ($14.52g\;dry\;wt.\;m^{-2}$). On the basis of the biomass, the Ecklonia cava was a representative species, distributed widely in the subtidal zone of the three islands (Yeoseodo, Geomundo, Baekdo). Also, the Sargassum sp. was dominant at Sejondo and Hongdo. The turbidity and light transmittance was divided into two groups. The seaweed community structure of group A (Byeongpungdo, Sejondo, Geomundo) was characterized by high turbidity, low light transmittance and a lower habitat depth than were observed in group B (Hongdo, Baekdo, Yeoseodo). As the water depth increased, the biomass decreased due to the lowered light transmittance. In Byeongpungdo and Sejondo, which showed high turbidity and low light transmittance, the degree of seaweed coverage was decreased with the depth of water. The ESGII ratio of the Ecological Status Group was higher than fourty percentage in Byeongpungdo and Baekdo. Community indices were as follows: dominance index (DI) 0.35-0.90, richness index (R) 7.03-17.93, evenness index (J′) 0.22-0.60, and diversity index (H′) 0.79-2.18. The Macroalgal zonation of the subtidal zone was calculated by the Ecklonia cava and Brown algal population on five islands(Byeongpungdo, Yeoseodo, Geomundo, Beakdo, Hongdo). On the other hand, Undaria pinnatifida and Sargassum sp. dominated at Sejondo. Additionally, the biomass ratio and the species richness of green algae was lower in group A. These differences in the seaweed community structure may have resulted from the effects of turbidity and light transmittance.

• Journal of Microbiology and Biotechnology
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• 제33권4호
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• pp.419-429
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• 2023

Ultraviolet C (UV-C, 200-280 nm) light has germicidal properties that inactivate a wide range of pathogenic and spoilage microorganisms. UV-C has been extensively studied as an alternative to thermal decontamination of fruit juices. Recent studies suggest that the efficacy of UV-C irradiation in reducing microorganisms in fruit juices is greatly dependent on the characteristics of the target microorganisms, juice matrices, and parameters of the UV-C treatment procedure, such as equipment and processing. Based on evidence from recent studies, this review describes how the characteristics of target microorganisms (e.g., type of microorganism/strain, acid adaptation, physiological states, single/composite inoculum, spore, etc.) and fruit juice matrices (e.g., UV absorbance, UV transmittance, turbidity, soluble solid content, pH, color, etc.) affect the efficacy of UV-C. We also discuss the influences on UV-C treatment efficacy of parameters, including UV-C light source, reactor conditions (e.g., continuous/batch, size, thickness, volume, diameter, outer case, configuration/arrangement), pumping/flow system conditions (e.g., sample flow rate and pattern, sample residence time, number of cycles), homogenization conditions (e.g., continuous flow/recirculation, stirring, mixing), and cleaning capability of the reactor. The collective facts indicate the immense potential of UV-C irradiation in the fruit juice industry. Existing drawbacks need to be addressed in future studies before the technique is applicable at the industrial scale.

• 반도체디스플레이기술학회지
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• 제17권3호
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• pp.75-84
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• 2018

According to IHS, the overall display market is expected to grow at an average annual rate of 6% from $ 104 billion in 2016, to $ 138 billion in 2021. Among them, the OLED display panel will grow from $ 15 billion to $ 41 billion over the same period, forecasting a high annual growth rate of 22%. However, the refraction index, light leakage, bubble generation, adhesion deterioration, peeling phenomenon, moisture resistance, light transmittance, low turbidity. OCA (optically clear adhesive), which solves problems such as improving the resistance of the conductive film, is largely dependent on imported products. In addition, in 2016, the world market is worth KRW4.3 trillion, and the adhesive market has a large market effect. In this study, we tried to analyze the technical competitiveness of patent and thesis by classifying OCA (optically clear adhesive, optical adhesive) for display panel by curing method. As a result of the study, the amount of patents and papers in Korea was found to be superior to other competitors, but the quality level was low. In particular, it was found that the achievements of the papers in the hot melt field are lacking and the government should expand its support.

• 대한화장품학회지
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• 제49권2호
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• pp.159-167
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• 2023

이산화티타늄(TiO₂)은 일반적으로 선크림 제제에 사용되어 빛의 물리적 산란 작용에 의해 피부 표면을 보호하고 유해한 자외선(UV)의 침투를 방지한다. 그러나 불활성 미네랄 성분으로 인해 피부에 사용시 백탁현상을 유발할 수 있다는 단점이 있다. 또한 백탁현상을 없애기 위해 TiO₂ 입자를 나노화 하면 가시광선 투과율을 증가시켜 백탁 현상을 감소시키지만 알레르기 염증과 같은 심각한 피부 트러블을 유발할 수 있다. 이러한 문제를 극복하기 위해 본 연구에서는 산소 결핍 구조 및 질소량 제어를 이용하여 TiO₂의 밴드갭을 제어하고, 결과적으로 피부 맞춤형 유색 TiO₂를 개발하였다. 이는 백탁 현상을 감소시킬 수 있을 뿐만 아니라 활성산소를 유발하여 피부 노화를 촉진시키는 것으로 알려진 블루라이트를 효과적으로 차단할 수 있다. 본 연구에서 제안된 밴드갭 제어 TiO₂ 화합물은 저자극이고 스펙트럼이 넓으며 환경친화적이다. 또한 이는 자외선 차단제의 sun protection factor (SPF)를 획기적으로 향상시켜 블루라이트 차단 제품에 적용할 수 있을 것으로 기대된다.