• Journal of Environmental Science International
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• v.2 no.4
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• pp.279-289
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• 1993

Light qualities and three kinds of plant hormones, NAA, GA3 and BA were treated on maize seedlings to investigate the effect on formation of the chlorophyll-protein complexes. Each three kinds of plant hormones accelerated the chlorophyll proteins formation, particularly LHCP-1 and LHCP-3, but two kinds of hormonal combinations didn't promote these proteins accumulation under sun light condition. The formation of chlorophyll proteins of LHCP-1, CPA and LHCP-3 associated with PSII was promoted under red light compared to sun light, on the contrary the formation of chlorophyll proteins was not affected by white light. Plant hormones under red light induced chlorophyll proteins formation associated with PSII at early state of chloroplast development and two kinds of hormonal combinations under red light were very effective in accumulation of chlorophyll proteins of PSII in contrast to sun light. The results obtained suggest that light may play an important role compared to plant hormones in the formation of chlorophyll proteins.

• Korean journal of applied entomology
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• v.10 no.1
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• pp.43-48
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• 1971

This experiment was conducted to determine the most effective type of Bight·trap for pine catepillar moths (Dendrolimus spectabilis B.) and to investigate the environmental factors affecting the attractiveness of the moths.. The various types of light traps made used of: black light, white light, fluorescent light, yellow light, and red light and the environmental factors considered were rainfall, wind velocity and collecting time. All the traps were operated from 8 in the evening to midnight. The results obtained are summarized as follows; The most effective attraction of moths ($62\%$ of total number attracted) was observed with blacklight-lamp and the most abundant attraction of the moths was found from 8 to 10 in the evening. Attractiveness in terms of sex ratio attracted from 8 to 10 in the evening was found to the .approximately 7 female to 1 male, Environmental factors considered were found to have no influences in attractiveness of the moths in this experiment.

• Journal of the Korean Wood Science and Technology
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• v.48 no.4
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• pp.548-561
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• 2020

Paecilomyces japonica is widely cultured to produce mycelium for medicinal and health food use. Illumination is an important factor in the growth and production of mycelium in submerged culture. The effects of different light-emitting diode (LED) combinations on the growth and cordycepin content as bioactive substances of mycelium were investigated. The results showed that the mycelium dry weights were lower under dark condition and red LED treatments. Dark condition, fluorescent light, and ultraviolet-A failed to increase the cordycepin content. Blue light was necessary to increase the cordycepin content, and a red-to-blue ratio of 3:7 induced the highest cordycepin content. The cordycepin contents of mycelium in submerged culture were significantly higher in a 12 h/day illumination time under red and blue (red-to-blue ratio of 3:7) LED treatments, showing an increase of up to 38% compared with those under the fluorescent-light control condition. The results demonstrated the roles of light with different wavelengths on the biosynthesis of cordycepin as bioactive substances. The low-heat release and replacement of traditional fluorescent lights with low-energy-consuming LEDs could increase the contents of bioactive substances. After optimization of the cordycepin production using response surface methodology (Box-Behnken design) to its canonical form, the optimum combination was found to be as follows: illumination time = 17.7 h/day, sugar content in the medium = 9.7 g/50 mL, and incubation time = 61.2 h. The model predicted a maximum response of 3779.2 ㎍/mL cordycepin yield.

• Journal of Environmental Science International
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• v.29 no.12
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• pp.1213-1222
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• 2020

In the current study, a Cu2O/TiO2 photoinduced nanocomposite materials prepared by ultrasonification method was evaluated the photocatalytic oxidation efficiency of volatile organic compounds (BTEX) under visible-light irradiation. The results of XRD confirmed the successful preparation of photoinduced nanocomposite materials. However, diffraction peaks belonging to TiO2 were not confirmed for the Cu2O/TiO2. The possible reason for the absence of Cu2O peak is their low content and small particle size. The result of uv-vis spectra exhibited that the fabricated Cu2O/TiO2 can be activated under visible light irradiation. The FE-SEM/EDS and TEM showed the formation of synthesized nanocomposites and componential analysis in the undoped TiO2 and Cu2O/TiO2. The photocatalytic oxidation efficiencies of benzene, toluene, ethylbenzene, and o-xylene with Cu2O/TiO2 were higher than undoped TiO2. According to light sources, the average oxidation efficiencies for BTEX by Cu2OT-0.5 were exhibited in the orer of 8 W day light > violet LEDs > white LEDs. However, the photocatalytic oxidation efficiencies normalized to supplied electric power were calculated to be in the following order of violet LEDs > white LEDs > 8 W day light, indicating that the LEDs could be a much more energy efficient light source for the photo-oxidation of gaseous BTEX using Cu2O/TiO2.

• Journal of Environmental Science International
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• v.33 no.8
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• pp.575-581
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• 2024

Insect pests are a significant threat to stored crops and can lead to considerable economic losses and reduced crop quality. Traditional pest control methods often involve chemical treatments, which have adverse environmental and health effects. This study evaluated the effectiveness of controlling the environment using LED lighting and plant-derived odor barriers as a dual strategy for insect pest control. The storage environment was altered using LED lights that emitted specific wavelengths (580-585 nm) and by reducing other wavelengths (300-500 nm). This light environment was combined with an insect odor barrier derived from Cinnamomum verum, Illicium verum, and Artemisia annua, and their duel impact on the behavior and frequency of insect pests under real storage conditions was determined. The findings revealed significant changes in the frequencies of various insect orders, indicating differential responses to light wavelengths and odor barriers. Notably, the introduction of an anti-insect light and odor barrier environment reduced Diptera and Hemiptera frequencies, which could potentially reduce pest intrusion. The results underscore the potential use of integrated light and odor barriers as a noninvasive and environmentally friendly approach to pest management. This study identifies the specific wavelengths and odor combinations that effectively deter insect pests and contribute to the development of more efficient and sustainable pest control methods. It also highlights the importance of understanding insect behavior and frequency changes in response to novel deterrent strategies.

• Journal of Photoscience
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• v.9 no.2
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• pp.150-153
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• 2002

Solar UV light is a well-known carcinogen. UVA radiation is probably carcinogenic to humans. In addition, recent investigations point to the importance of UVA irradiation in the photoaging. We investigated the mechanism of sequence- specific DNA damage using $\^$32/P-Iabeled DNA fragments in relation to carcinogenesis and aging. Furthermore, we investigated whether UVA accelerates the telomere shortening in human WI-38 fibroblasts. The exposure of double- stranded DNA fragments to 365 nm light in the presence of endogenous sensitizers produced sequence-specific cleavage at the 5' site of 5'-GG-3' and 5'-GGG-3' sequences. In addition, HPLC analysis revealed that sensitizers plus 365 nm light increased the 8-oxodG content of double-stranded DNA. We discuss the mechanisms of guanine-specific DNA damagecaused by excited photosensitizers in relation to carcinogenesis and aging.

• Wind and Structures
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• v.19 no.6
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• pp.603-621
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• 2014

Past high speed wind events have exposed the vulnerability of the roof systems of existing light-framed wood structures to uplift loading, contributing greatly to economic and human loss. This paper further investigates the behaviour of light-framed wood structures under the uplift loading of a realistic pressure distribution. A three-dimensional finite-element model is first developed to capture the behaviour of a recently completed full-scale experiment. After describing the components used to develop the numerical model, a comparison between the numerical prediction and experimental results in terms of the deflected shape at the roof-to-wall connections is presented to gain confidence in the numerical model. The model is then used to analyze the behaviour of the truss system under realistic and equivalent uniform pressure distributions and to perform an assessment of the use of the tributary area method to calculate the withdrawal force acting on the roof-to-wall connections.

• Journal of the Speleological Society of Korea
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• no.85
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• pp.15-17
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• 2008

This paper is attempted to review a cave restoration and preservation plan against environmental destruction and pollution as a preliminary survey for preservation of cave environment. Consequently, it's important to throw an indirect light rather than direct light on cave formations, keeping distance of 2m at least. The already existing moss should be removed using wet cloth or sponge as soon as possible. If it's washed off, be careful not to splash it or water on nearby subjects. Based on an automatic switch-off system, light will automatically turn off when no one is left in the cave. It's also recommended to dualize the cave passage and partially close the cave by taking turns to give a time to recover.

• Journal of Korean Society on Water Environment
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• v.20 no.6
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• pp.577-582
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• 2004

The photocatalytic degradation of atrazine and PCP, a endocrine disruptors, has been investigated over $TiO_2$ photocatalysts under ultraviolet (UV) light irradiation. The effect of operational parameters, i.e., pH, light intensity and persulphate concentration on the degradation rate of aqueous solution of atrazine and PCP has been examined. The results presented in this work demonstrate that, as pH and the light intensity increased, the photocatalytic reaction rates were enhanced. Individual use of $TiO_2$-persulphate was far more effective than using only $TiO_2$ in atrazine and PCP removal. Based on the overall experimental results, the photocatalytic oxidation of atrazine and PCP with the coated $TiO_2$ photocatalyst is found to be very effective under the operational conditions delineated in this study.

• Bulletin of the Korean Chemical Society
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• v.33 no.7
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• pp.2309-2314
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• 2012

Ag deposited N-$TiO_2$ composite nanoparticles were prepared via $NH_3$ plasma treatment. X-ray diffraction, UV-vis spectroscopy, photoluminescence, and X-ray photoelectron spectroscopy were used to characterize the prepared $TiO_2$ samples. The plasma treatment did not change the phase composition and particle sizes of $TiO_2$ samples, but extended its absorption edges to the visible light region. The photocatalytic activities were tested in the degradation of an aqueous solution of a reactive dyestuff, methylene blue, under visible light. The photocatalytic activities of Ag deposited N-$TiO_2$ composite nanoparticles were much higher than Ag-$TiO_2$, N-$TiO_2$, and P25. A possible mechanism for the photocatalysis was proposed.