• Korean Journal of Weed Science
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• v.5 no.1
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• pp.19-23
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• 1985

Soil temperature was higher in clear or blue polyethylene film and bare soil than in black or green polyethylene film and straw mulching. Light transmission was low in black, blue or green colored polyethylene film and straw mulching. Germination of weeds was generally high under clear polyethylene film but black polyethylene film inhibited the germination. Germination of Portulaca oleracea, Setaria viridis and Amaranthus retroflexus increased under blue polyethylene film but inhibition of germination was observed in Erigeron canadensis, Avena fatua, Chenopodium ablum, Digitaria sanguinalis and Echinochloa crusgalli. Green polyethylene film mostly inhibited germination of weeds except A, fatua, C. album and E. canadensis. The greatest number of weeds emerged was obtained in clear polyethylene film, next in bare soil but green or blue polyethylene film inhibited the emergence of weeds. However, no emergence of weeds was observed under black polyethylene film. The highest dry weight of weeds was obtained in clear polyethylene film, next in bare soil, but green or blue polyethylene film and straw mulching caused suppression of weed growth. No weeds were grown under black polyethylene film.

• Bulletin of the Korean Chemical Society
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• v.29 no.7
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• pp.1323-1325
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• 2008

The acetylene black (AB) was dispersed into water in the presence of dihexadecyl hydrogen phosphate (DHP) via ultrasonication, resulting in a stable and well-distributed AB/DHP suspension. After evaporation of water, an AB/DHP composite film-modified electrode was prepared. The electrochemical responses of $K_3$[Fe$(CN)_6$] at the unmodified electrode, DHP film-modified electrode and AB/DHP film-modified electrode were investigated. It is found that the AB/DHP film-modified electrode possesses larger surface area and electron transfer rate constant. Furthermore, the electrochemical behaviors of 1-naphthylacetic acid (NAA) were examined. At the AB/DHP film-modified electrode, the oxidation peak current of NAA remarkably increases. Based on this, a sensitive and convenient electrochemical method was proposed for the determination of NAA. The linear range is in the range from $4.0 {\times} 10^{-8}\;to\;5.0 {\times} 10^{-6}$ mol $L^{-1}$, and the detection limit is $1.0 {\times} 10^{-8}$ mol $L^{-1}$. Finally, this new sensing method was employed to determine NAA in several soil samples.

• Korean Journal of Agricultural and Forest Meteorology
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• v.13 no.1
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• pp.1-9
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• 2011

This study was conducted to investigate the influence of different polyethylene film (P.E. film) for mulching on the changes in soil temperature and the production of good feathered apple nursery trees. M.9 rootstocks with stem diameter of 9.1~11.0 mm were planted in plots covered with different P.E. film (i.e., transparent P.E. film, black P.E. film, and bare soil as control). Three weeks after planting, the rootstocks were veneer grafted with 'Sinano Sweet' apple cultivar. In the middle of June, BA was sprayed to nursery for inducing feathering during the growing season. The soil temperature of the control was higher than air temperature by about $0.7^{\circ}C$ from mid April to early October, and that of P.E. film mulching was about $1{\sim}5^{\circ}C$ higher than that of the control. The soil temperature under transparent P.E. film was about $2{\sim}3^{\circ}C$ higher than that under black P.E. film. The diurnal range of soil temperature under the black P. E. film was lowest among all treatments. The P.E. film mulching induced better tree growth and feathering than bare soil. Percentage of good feathering apple nursery of black P.E. film was highest among all treatments because the soil temperature unuder black P.E. film in the early growing season was higher than that of the control and the number of days when the maximum soil temperature was over $35^{\circ}C$ in the summer was lower than that under the transparent P.E. film.

• Solar Energy
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• v.7 no.2
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• pp.65-73
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• 1987

Microstructural basis for the thermal degradation of electrodeposited black chrome "solar-L-foil" heated in air has been investigated using scanning electron microscopy, energy dispersive x-ray analysis, X-ray diffraction techniques and UV-VIS-NIR spectre-photometer. Experimental result, the change in the shape of the particle comprising the film from their initial needle like structure to a more spherical shape with an oxide after 1hr annealing at $600^{\circ}C$ has been observed. The effect is to degrade solar absorptance of the thin film.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.08a
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• pp.236-241
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• 1999

The characteristics of the deterioration and oxidation of high speed steel(

• Korean Journal of Plant Resources
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• v.9 no.2
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• pp.177-181
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• 1996

This study was carried out to obtain basic data for technical inprovement about cultivation according to micrometerological changes under various mulching materials in Dendropanox morbifera LEV. The results are summarized as follows. Transparent polyethylene film and black polyethylene film mulching materials increased the soil porosity and reduced change of the soil moisture content. The rate of missing plant during overwinter increased in the control plot. Growth of Dendropanox morbifera LEV, was accelerated by transparent polyethylene film and black polyethylene film mulched.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.272-274
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• 2002

The contribution of light in high-energy film dosimetry was examined using six commercially available solid water substitute phantoms. As six commercially available phantoms; RMI-451, Mix-DP, WE211, WE211-Black, PMMA and PMMA Black were evaluated in this study. It is difficult to evaluate the contribution of Cerenkov radiation and the optical permeability to the relative and/or absolute dosimetry using unpacked film in these phantoms. Therefore the contribution of Cerenkov radiation was estimated by the comparison between film densities in the shielded side (shutting off the light) and unshielded sides on a phantom. The effect of optical permeability was measured under ambient light by the time scale method. The results suggest that the use of black colored phantoms may improve the accuracy of dose measurement in film dosimetry.

• Korean Journal of Medicinal Crop Science
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• v.12 no.1
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• pp.85-88
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• 2004

This study was carried out to obtain basic information on cultivation of Curcuma longa L. in southern part of Korea. The results were summaried as follows. Mulching of both transparent polyethylene film and black polyethylene film improved the soil characters such as soil porosity and soil moisture content. The rate of emergency after winter was increased by mulching. Growth of Curcuma longa L. was accelerated by mulching of transparent polyethylene film and black polyethylene film mulched.

• Korean Journal of Plant Resources
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• v.12 no.3
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• pp.179-185
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• 1999

The study which was conducted to determine the effects of the polyethylene film on the culture of Pleurotus ostreatus is summarized in the following: 1) The fresh weight of Pleurotus ostreatus cultured by the box culture method mulching with black polyethylene film was 2,237g/box and, 2,028g/box by white polyethylene film mulching, and 1,695g/box at the conventional culture which was by 24.2% and 16.4% higher than that of the conventional culture.2) The fresh weight of P. ostreatus cultured by the shelf culture method mulching with the black polyethylene film was 17.4kg/m$^2$ at the white polyethylene film culture, 14.6kg/m$^2$ at the conventional culture which was by 16.2%, 7.5% higher than that of the conventional culture. 3) The best shape appearance in terms of the diameter in P. ostreatus was 5~30mm and the intervals were 10cm respectively. 4) The black polyethylene film mulching in P. ostreatus observed in good protection against Pseudomonas spp., Trichoderma, or mushroom flies. 5) The black polyethylene film mulching method for the culture of P. ostreatus was much better than that of the shelf-culture, box-culture or the sack culture in terms of total yield and quality. 6) The length of harvesting implement of P. ostreatus was suitable for 45~120cm in order to use on the harvest of the mulching.

• Korean Journal of Plant Resources
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• v.7 no.2
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• pp.183-186
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• 1994

This study was conducted to investigate desirable storage method to major chinese herbal medicine materials, Moutan Radicis Cortex in different packing materials and sealing degree. The loss in weight of Moutan Radicis Cortex as influenced by packing materials was the lowest at complete sealing treatment with transparent or black polyethylene film. The rot ratio of Moutan Radicis Cortex during the storage period was not difference between packing materials, transparent and black polyethylene film, but rot ratio of complete sealing condition was lower than punch ($\phi$J5mm) on polyethylene film.