• Journal of the Optical Society of Korea
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• 제12권4호
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• pp.221-225
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• 2008

We propose a simple hydrogen detection scheme based on a Mach-Zehnder interferometer formed with a pair of palladium-coated long-period fiber gratings (LPGs). Since an LPG pair offered a fine-structured interference fringe in its transmission spectrum, the resolution as a sensor could be appreciably enhanced compared to that of a single LPG. As the palladium layer absorbed hydrogen, the effective refractive indices of the cladding modes were increased so that the interference spectrum was blue-shifted up to 2.3 nm with a wavelength sensitivity of -0.29 nm/min for 4% of hydrogen concentration.

• Bulletin of the Korean Chemical Society
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• 제25권8호
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• pp.1202-1206
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• 2004

Novel naphthyl-containing biphenyl analogues were prepared by Suzki reaction for the chemiluminescent blue fluorophores. UV-Vis absorption, photoluminescence, chemiluminescence and CIE chromaticities were measured. The fluorophores displayed blue photoluminescence in solution with a maximum intensity around 378-415 nm. Sodium salicylate-catalyzed reaction of them with bis(2 carbopentyloxy-3,5,6-trichlorophenyl)-oxalate with hydrogen peroxide provided a strong chemiluminescent red light emission with wavelengths of 398-427 nm; these were similar to the photoluminescent spectra. The chemiluminescent intensity decayed exponentially and the glow of chemiluminescence, which was visible with naked eyes, was maintained for more than 4 h.

• 생명과학회지
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• 제27권12호
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• pp.1479-1485
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• 2017

일반적으로 노화, 영양부족 및 다양한 만성질환에 의하여 유발되는 근위축은 근육 단백질 합성 억제 및 분해증가를 통하여 근섬유 및 근육의 밀도를 감소시키는 것으로 알려져 있다. 본 연구에서는 근위축과 관련된 in vitro 실험을 위한 C2C12 근아세포에서 근관세포로의 분화과정을 확립하고, 분화가 유발된 C2C12 근관세포를 대상으로 dexamethasone 및 hydrogen peroxide에 의한 근위축 유발 및 관련 단백질들의 발현 변화를 조사하였다. 먼저 C2C12 근아세포에 분화배지를 처리하였을 경우 근관세포로 분화가 유발되었으며, 분화와 관련된 단백질인 myogenin 및 myoD의 발현이 증가하는 것으로 나타났다. 분화가 유발된 C2C12 근관세포에 세포독성이 없는 조건의 dexamethasone 및 hydrogen peroxide를 처리하였을 경우 근관의 지름이 감소하였으며, 이러한 현상은 musclespecific ubiquitin ligases인 MAFbx/atrogin-1 및 MuRF1의 발현 증가와 함께 muscle-specific transcription factor인 myogenin 및 MyoD의 발현 감소와 관련이 있다는 것을 확인하였다. 본 연구 결과는 근위축과 관련된 in vitro 실험 모델의 구축을 위한 최적의 분화조건 확립과 함께 dexamethasone 및 hydrogen peroxide를 근위축 유도제로 사용할 수 있는 가능성 을 제시하는 것이다.

• Environmental Engineering Research
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• 제22권1호
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• pp.108-115
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• 2017

Chlorination has been the most common antifouling method, but alternatives are under searching. In this article, we report how the hydrogen peroxide could enhance the effect of chlorination to prevent fouling by inhibiting larvae settlement and abatement of mussel colonization or by extinct of them; through marine mussel Mytilus edulis. The addition of hydrogen peroxide shows synergic effect on the veliger larvae (up to 19 folds) and effectively reduces required time of mussel mortality by 8-22%. For resolution of micro- and macro-fouling caused by the marine mussel, as well as diminishing of time and conventional chlorine dose could be important factor in favour of environment and economics.

• 웰빙융합연구
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• 제5권4호
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• pp.19-31
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• 2022

Purpose: This study was conducted to identify indoor air quality in various living spaces using sensors that can measure noise, vibration, fine dust, and odor in real time and to propose optimal indoor air quality maintenance management using Internet of Things(IoT). Research design, data and methodology: Using real-time sensors to monitor physical factors and environmental air pollutants that affect the comfort of the residential environment, Noise, Vibration, Atmospheric Pressure, Blue Light, Formaldehyde, Hydrogen Sulfide, Illumination, Temperature, Ozone, PM10, Aldehyde, Amine, LVOCs and TVOCs were measured. It were measured every 1 seconds from 4 offices and 4 stores on a small scale from November 2018 to January 2019. Results: The difference between illuminance and blue light for each measuring point was found to depend on lighting time, and the ratio of blue light in total illumination was 0.358 ~ 0.393. Formaldehyde and hydrogen sulphide were found to be higher than those that temporarily attract people in an indoor office space that is constantly active, requiring office air ventilation. The noise was found to be 50dB higher than the office WHO recommendation noise level of 35 ~ 40dB. The most important factors for indoor environmental quality were temperature> humidity> illumination> blue light in turn. Conclusions: Various factors that determine the comfort of indoor living space can be measured with real-time sensors. Further, it is judged that the use of IoT can help maintain indoor air quality comfortably.

• 한국어병학회지
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• 제26권1호
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• pp.31-38
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• 2013

The edible ascidian, Halocynthia roretzi is a commercially important fisheries resource in Korea. However, there have been outbreaks of mass mortality due to soft tunic syndrome. It was discovered recently that the cause of death is infection by a protozoan parasite Azumiobodo hoyamushi. Alamar blue assay and microscopic counting were used to estimate anti-protozoal effects of 20 drugs having different action mechanisms. Through comparison of alamar blue assay and microscopic counting, 6 drugs were found to be potential in protozoan-killing effects: amphotericin B, formalin, hydrogen peroxide, bithionol, benzalkonium chloride, bronopol (24hr-$EC_{50}{\leq}20{\mu}g/ml$). The preliminary data can be used as a basis to develop anti-protozoal agents against A. hoyamushi.

• Bulletin of the Korean Chemical Society
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• 제24권7호
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• pp.961-966
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• 2003

A quantum-chemical study of conformations and electronic structures of polyheterocyclic derivatives with vinylenediheteroatom substituents at the 3- and 4-positions was performed to search for novel blue-lightemitting conjugated polymers. Conformational potential energy curves of the polymers were constructed as a function of the helical angle (a) through semiempirical Hartree-Fock band calculations at the Austin model 1 level. It is found that poly(3,4-vinylenedioxythiophene) possesses a quite flat curve in the range of α = 51.4°- 120°. Replacing S atoms for O atoms greatly increases repulsion between the neighboring units, and thereby the units become perpendicular to one another. Because of the hydrogen bonding between O and NH, poly(3,4- vinylenedioxypyrrole) is predicted to be anti-coplanar and poly(3,4-vinylenediaminofuran) to be nearly anticoplanar. According to the modified extended Huckel band calculations, the HOMO-LUMO gaps (HLGs) of the polymers, unless the polymer chains are twisted, are close to or slightly smaller than those of their respective mother polymers. Among the polymers, poly(3,4-vinylenedioxythiophene) is presumed to be the most probable candidate for a blue-light emitter because its HLG is within the range of the electronic requirement for blue-light emitters.

• 신재생에너지
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• 제19권2호
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• pp.13-22
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• 2023

With the increased interest in renewable energy, various hydrogen production technologies have been developed. Hydrogen production can be classified into green, blue, gray, and pink hydrogen depending on the production method; each method has different technical performance, costs, and CO₂ emission characteristics. Hence, selecting the technology priorities that meet the company strategy is essential to develop technologically and economically feasible projects and achieve the national carbon neutrality targets. In addition, in early development technologies, analyzing the technology investment priorities based on the company's strategy and establishing investment decisions such as budget and human resources allocation is important. This study proposes a method of selecting priorities for various hydrogen production technologies as a specific implementation plan to achieve the national carbon neutrality goal. In particular, we analyze key performance indicators for technology, economic feasibility, and environmental performance by various candidate technologies and suggest ways to score them. As a result of the analysis using the aforementioned method, the priority of steam methane reforming (SMR) technology combined with carbon capture & storage (CCS) was established to be high in terms of achieving the national carbon neutrality goal.

• 대한금속재료학회지
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• 제47권2호
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• pp.91-98
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• 2009

The titania nanotubular layer for photocatalytic application was synthesized by anodization process in HF solution and the photocatalytic efficiencies of nanotubular film were evaluated by the decomposition rate of aniline blue. In order to facilitate the photocatalytic reaction, the electron acceptors such as potassium bromate, hydrogen peroxide and ammonium persulfate were added to aniline blue solution and the effects of electron acceptors on the dye degradation efficiency were evaluated. The results showed that the photocatalytic efficiency has markedly improved by adding the electron acceptors.

• 한국세라믹학회지
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• 제25권4호
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• pp.408-414
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• 1988

This thesis is 2nd thesis from "Mechanism of Intercalation Compounds in Graphite with Hydrogen sulfate(J. Korea Cer. Soc. Vol. 22. No.6, 1985). We have oxidized natural Graphite flakes(0.1~0.2mm., Kropfm hl passau in Deutchland. S40) with a solution of CrO3 in H2SO4. Whilst persulfate ions were intercalated, too, below 7$^{\circ}C$, no evidence for intercalation of a peroxo compound was found at 22$^{\circ}C$. The reaction was interrupted after various times by filtering and washing with concentrated H2SO4. X-ray diffraction showed that the 2nd stage compound had already been formed after 2 minutes. We could only follow further oxidation to the blue stage compound which was completed after 35 minutes. We have found six distinct intermediate stage between 2nd stage and 1 stage. Experiments are described on the formation of intermediate stage color and X-ray diffraction analysis.ysis.