• Elastomers and Composites
• /
• v.51 no.1
• /
• pp.31-37
• /
• 2016

In this study, we studied the photocatalytic functionality such as deodorant, antibacterial, antistatic of polyester fabrics treated with visible-light responsive photocatalyst. According to UV/visible spectrometry result, the UV-visible peak of visible-light responsive photocatalyst was found to be red shift at 420 nm sensitive in the visible light region. Also, the deodorizing and antimicrobial performance were shown to be retained more than 99% both before washing and even after 25 times washing. According to washing durability of polyester fabrics treated with visible-light responsive photocatalyst, the reduction effects for gas such as ammonia, trimethylamine, formaldehyde and toluene after 25 times washing appeared to be retained as much as before washing. At both before washing and after 25 times washing, antistatic property showed frictional voltage of approximately 250V.

• Elastomers and Composites
• /
• v.48 no.3
• /
• pp.209-215
• /
• 2013

On this study, visible-light responsive photocatalyst prepared by sol-gel method was evaluated the effect of the reduction of volatile organic compounds (VOCs) occurred in vehicle interior and its property was examined. According to UV/visible result, visible-light responsive photocatalyst was found that the UV-visible peak is red shift at 420nm, is sensitive in the visible light region. With vehicle interior parts and materials coated visible-light responsive photocatalyst, VOCs was measured by GC/MS. Measuring the VOCs generated from vehicle interior parts and materials, the reduction of VOCs was confirmed.

• Rapid Communication in Photoscience
• /
• v.2 no.1
• /
• pp.9-17
• /
• 2013

Visible light-sensitive $TiO_2$ and ZnO nanostructure materials have attracted great attention as the promising material for solar energy conversion systems such as photocatalysts for water splitting and environmental purification as well as nano-biosensors. Success of their applications relies on how to control their surface state behaviors related to the exciton dynamics and optoelectronic properties. In this paper, we briefly review some recent works on single nanoparticle photoluminescence (PL) technique and its application to observation of their surface state behaviors which are raveled by the conventional ensemble-averaged spectroscopic techniques. This review provides an opportunity to understand the temporal and spatial heterogeneities within an individual nanostructure, allowing for the potential use of single-nanoparticle approaches in studies of their photoenergy conversion and nano-scale optical biosensing.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2018.05a
• /
• pp.641-642
• /
• 2018

LED-based visible light communication requires separate transmission and reception equipment and is capable of communication only in the range of the light source. Also, there is an advantage that it can be used in a frequency sensitive area using a visible light band. Research is needed to apply these advantages and characteristics to various fields. In this paper, we implemented and verified the functions of the visible light communication system using broadcast methods.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.5
• /
• pp.3131-3138
• /
• 2015

At a dermatology during the skin care, photodynamic therapy(PDT) is carried after 5-aminolevulinic acid(ALA), light sensitive material, is applied. At a skin care shop, using drug is prohibited. Thus, the aim of this research was to see the effect of the acne skin by irradiating PDT to the skin without applying ALA. The research method was that 24 female undergraduates who had acne on their face at the level of mild or comedonal, and the participants were divided into four groups(group1: no treatment, group 2: 420 nm of blue visible light, group 3: 660 nm of red visible light and group 4: blue and red visible light). The participants of group 2, 3 and 4 were irradiated with visible light for 20 minutes per week for 6 weeks, and they were compared to group 1. As a result of the research, the number of erythema, sebum, papules and pustules of those who were irradiated with visible light decreased, and the pore size of those also decreased while the amount of moisture increased. If an skin care shop applies PDT to the existing acne skin care, that PDT will influence on the program of a skin care shop is expected.

• Journal of Photoscience
• /
• v.2 no.1
• /
• pp.31-35
• /
• 1995

Light signals in the form of intensity gradient, propagation direction, and wavelength elicit diverse mechanical responses ("photomechanical responese") in most organisms. The single cell ciliates, Stentor coeruleus and Blepharisma japonicum, are particularly sensitive to the light of visible wavelengths. In this paper, the way in which the seemingly sophisticated light signal transduction is triggered by the photosensory apparatus will be described in terms of the photoreceptor structure and photochemical function.

• Journal of the Korean Chemical Society
• /
• v.68 no.5
• /
• pp.299-302
• /
• 2024

• Elastomers and Composites
• /
• v.51 no.3
• /
• pp.226-232
• /
• 2016

We studied the photocatalytic functionality such as deodorant, antibacterial, fine dust collection efficiency of polyester-based non-woven fabric filter treated with self-actuated photocatalyst. According to UV/visible result, the UV-visible peak of visible-light responsive photocatalyst was found to be red shift at 420 nm sensitive in the visible light region. The deodorizing performance was shown to be reduced more than 80% even without dark conditions. Fine dust particles collection efficiency was shown to be excellent at the size of not only $2.5{\mu}m{\sim}10.0{\mu}m$ but also less than $2.5{\mu}m$. Also antimicrobial and antifungus was shown to be reduced more than 99.9%.

• Proceedings of the Korean Society of Plant Pathology Conference
• /
• 2003.10a
• /
• pp.93.1-93
• /
• 2003

A growth chamber fumigation was conducted to evaluate the ozone (O3) on the physiology of three hot pepper, Capsicum annuum L. cultivars, 'dabotab', 'buchon' and 'pochungchun'. Thirty-day old plants were exposed to O3 of 120 nl 1-1 in the chambers for 8 h d-1 for 3 days. Foliar damage due to O3 was different from the varieties, 'dabotab'was most sensitive to O3, 'pochungchun' was medium, and 'buchon' was resistant. Ozone symptom on the leaves was bifacial necorsis. Photosynthesis and stomatal conductance were decreased due to O3 treatment, but they were not much different from the variety. Decreases of net photosynthesis by O3 were 56％, 40％ and 35％ on 'dabotab', 'buchon' and 'pochungchun', respectively Decreases of stomatal conductance by O3 were 66％, 63％, and 50％ on each varieties. Ozone closed the stomata and decrease net photosynthesis on hot peppers regardless of the variety. Light curves on the three varieties were showing similar patterns that O3 damage on net photosynthesis were started at the low levels of light with or without the visible injury, Assimilation-internal CO2 concentration curves of the three cultivars were not different due to the treatment. It means there was not significant biochemical damage Inside the leaves by O3. In conclusion, ozone closed the stomata and damaged light capturing system of the pepper leaves with or without the visible damage. Although visible damage of the leaves could be a good indicator of O3 resistance, the ecophysiological change by O3 were not proportional to the amout of visible injuries

• Journal of Powder Materials
• /
• v.24 no.6
• /
• pp.477-482
• /
• 2017

Nitrogen-doped titanium dioxide (N-doped $TiO_2$) is attracting continuously increasing attention as a material for environmental photocatalysis. The N-atoms can occupy both interstitial and substitutional positions in the solid, with some evidence of a preference for interstitial sites. In this study, N-doped $TiO_2$ is prepared by the sol-gel method using $NH_4OH$ and $NH_4Cl$ as N ion doping agents, and the physical and photocatalytic properties with changes in the synthesis temperature and amount of agent are analyzed. The photocatalytic activities of the N-doped $TiO_2$ samples are evaluated based on the decomposition of methylene blue (MB) under visible-light irradiation. The addition of 5 wt% $NH_4Cl$ produces the best physical properties. As per the UV-vis analysis results, the N-doped $TiO_2$ exhibits a higher visible-light activity than the undoped $TiO_2$. The wavelength of the N-doped $TiO_2$ shifts to the visible-light region up to 412 nm. In addition, this sample shows MB removal of approximately 81%, with the whiteness increasing to +97 when the synthesis temperature is $600^{\circ}C$. The coloration and phase structure of the N-doped $TiO_2$ are characterized in detail using UV-vis, CIE Lab color parameter measurements, and powder X-ray diffraction (XRD).