• Korean Journal of Plant Resources
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• v.9 no.2
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• pp.165-170
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• 1996

The study was carried out to identify the characteristics of leafy shapes, and to establish the cultural practices such as shading condition, fertilization method, and planting distance of Cirsium nipponicum. Leaf shapes in this plant consist of two kinds, lobation and non-lobation which has two spur type showing large and small spur. Protein band patterns showed that a new protein band in non-lobation with large spur was appeared at the 116.4kDa. For shading condition and fertilization method, number of stems in non-shading and organic matter treatment was higher than that of shading 55% with 3.7. Fresh leaf yield on non-shading and organic matter treatment was higher than that of other treatments. Growth characteristics of leaf number was increased in the $60\times30cm$ treatment, but was redeuced to some extent compared with $60\times45cm$. To increase the fresh leaf yield, the optimum planting distance was $30\times20cm$ with 4,100kg/10a.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.5
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• pp.182-187
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• 2015

The growth and characterization of micro sized AlGaN array structures selectively grown by metal organic chemical vapor deposition (MOCVD) on GaN stripes are reported. The shape of the AlGaN array structures depends on the size of exposed area for selective growth. The AlGaN array structures grown selectively on relatively large exposed area have regular shapes resembling those of the GaN stripes on the substrate, while samples selectively grown on relatively small exposed area have irregular shapes. The phonon frequency of the AlGaN array structures increases with increasing Al composition in the AlGaN structure. However, at relatively high Al composition (x = 0.28 in this research), the phonon frequency decreases slightly from the expected value not only because of large tensile strain associated with large differences between the lattice constants of the AlGaN structure and underlying GaN stripes but also changes of crystal facet direction during the selective growth.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.5
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• pp.344-349
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• 2015

A new information society of late has arrived by the rapid development of various information & communications technologies. Accordingly, mobile devices which are light and thin, easy and convenient to carry on the market. Also, the requirements for the larger television sets such as fast response speed, low-cost electric power, wider visual angle display are sufficiently satisfied. The currently most widely studied display material, the Organic Light-emitting Diodes(OLEDs) overwhelms the Liquid Crystal Display(LCD), the main occupier of the market. This new material features a response speed of more than a thousand times faster, no need of backlight, a low driving voltage, and no limit of view angle. And the OLEDs has high luminance efficiency and excellent durability and environment resistance, quite different from the inorganic LED light source. The OLEDs with simple device structure and easy produce can be manufactured in various shapes such as a point light source, a linear light source, a surface light source. This will surely dominate the market for the next generation lighting and display device. The new display utilizes not the glass substrate but the plastic one, resulting in the thin and flexible substrate that can be curved and flattened out as needed. In this paper, OLEDs device was produced by changing thickness of Teflon-AF of hole injection material layer. And as for the electrical properties, the four layer device of ITO/TPD/$Alq_3$/BCP/LiF/Al and the five layer device of ITO/Teflon AF/TPD/$Alq_3$/BCP/Lif/Al were studied experimentally.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.17 no.2
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• pp.57-62
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• 2007

Willemite green phosphor powders have been prepared by the metallo-organic decomposition (MOD) method, and the photoluminescence and phase formation were studied as a function of both the firing temperature ($800{\sim}1100^{\circ}C$) and the concentration of Mn activator ($4{\sim}12 mol%$). Under 254 nm excitation source, the emission intensity of the phosphors increased with increasing the firing temperature from 800 to $1000^{\circ}C$. From the XRD analysis, the powders heat-treated above $1000^{\circ}C$ showed willemite crystal structure. The maximum emission intensity was obtained far the phosphors heat-treated at $1000^{\circ}C$ with 8 mol% of Mn content. The concentration quenching was occurred when the Mn concentration exceeded 10 mol%. The phosphor particles showed spherical shapes with the average size of $0.4{\sim}0.5{\mu}m$ by the SEM morphology.

• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.757-766
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• 2015

This study was considered chances of additional income, if farmers raised silkworms in unused mulberry leaves, after harvesting mulberry, investigated yields of mulberry leaves in vinyl-house and optimal amount in raised silkworms, First, the results was investigated productions of mulberry leaves in the mulberry tree-shape of vinyl-house, T-shape harvested 7.07 kg, Y-shape was 6.55 kg, in comparison with convention of it was harvested 4.75 kg mulberry leaves/1 mulberry tree, was harvested 49%, 38% more each. Also, yields of mulberry leaves was used 302 kg when was raised 1box of silkworms in the mulberry tree-shape of vinyl-house. In other hand, yields of raising silkworms was analysed in the mulberry tree-shapes of vinyl-house, mulberry leaves of $1,000m^2$ vinyl-house mulberry tree was raised average of 3.74 boxs silkworms, in the concrete conventional-shape was 3.24 boxs, T-shape did 4.17 boxs and Y-shape was 3.83 boxs, Consequently, if the farmers of $1,000m^2$ vinyl-house mulberry tree raised silkworms with unused mulberry leaves, could get 1~1.2 million won additionally.

• Korean Institute of Interior Design Journal
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• v.25 no.4
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• pp.90-97
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• 2016

As the paradigm which emphasizes nurturing creative elites is introduced, more attention has been paid to children playing and their creativity. This change means that the importance of creativity is emphasized in the education of children, and furthermore, playgrounds which focus on creativity and imagination are needed. Therefore, this study examines the spatial characteristics of playgrounds for children and suggested strategies to improve them. There are five spatial characteristics of a creative playground: aesthetics, being eco-friendly, exploration, challenging and variable. Through the five characteristics, playgrounds were analysed based on ten expressive elements and the results are summarized: Creative playgrounds for children should have an attractive design with sculptural elements which stimulate children to be excited through associable shapes and abstract colors. Second, shelter type structures and a flexible flow design are needed so that children can feel free and be encouraged to explore in diverse ways. Third, as playgrounds for children provide spaces for rest in addition to play, organic facilities and eco-friendly materials for the rest space should to be used. Fourth, as childhood is a period when emotional, cognitive and physical development are achieved, organic geographical features and atypical facilities should be provided so that children can acquire extensive skills and join in physical activities. Finally, creative playgrounds for children should have mobile or variable facilities which consider the characteristics of children who want to do diverse activities and play different games. This study analysed playgrounds for children and suggested strategies to improve them. For successful design and use of creative playgrounds, it is suggested that intensive research on them and consultation with experts should be considered.

• Journal of Food Hygiene and Safety
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• v.32 no.5
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• pp.443-446
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• 2017

This study investigated the physical properties of polymers and antimicrobial activities of organic acids on Listeria monocytogenes to develop hydrogels. ${\kappa}-carrageenan$ (1, 2, and 3%), carboxymethylcellulose (CMC; 1, 3, and 5%), and agar (1.5 and 3%) were mixed with cross-linkers ($Na^+$, $K^+$, $Ca^{2+}$, and $Al^{3+}$) or each other by stirring or heating to form cross-linkage, and their physical properties (hardness, elasticity, and swelling) were measured. The hydrogels formulated with organic acid (1, 3, and 5%) were analyzed by spot assay against L. monocytogenes. ${\kappa}-carrageenan$ formed hydrogels with high hardness without other cross-linkers, but they had low elasticity. The elasticity was improved by mixing with other cross-linkers such as $K^+$ or other polymer, especially in 3% ${\kappa}-carrageenan$. CMC hydrogel was formed by adding cross-linkers $Al^{3+}$, $Na^+$, or $Ca^{2+}$, especially in 5% CMC. Thus, stickiness and swelling for selected hydrogel formulations (two of ${\kappa}-carrageenan$ hydrogels and three of CMC hydrogels) were measured. Among the selected hydrogels, most of them showed appropriate hardness, but only 3% ${\kappa}-carrageenan-contained$ hydrogels maintained their shapes from swelling. Hence, 3% ${\kappa}-carrageenan+0.2%$ KCl and 3% ${\kappa}-carrageenan+1%$ alginate+0.2% KCl+0.2% $CaCl_2$ were selected to be formulated with lactic acid, and showed antilisterial activity. These results indicate that 3% ${\kappa}-carrageenan$ hydrogels formulated with lactic acid can be used to control L. monocytogenes on food surface.

• Asian Journal of Atmospheric Environment
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• v.7 no.1
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• pp.1-7
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• 2013

To establish the method for investigating the behavior of aerosol particles deposited on the leaf surface against fog water under natural conditions, scanning electron microscopy with energy-dispersive X-ray (SEM-EDX) analysis and wash water analysis by ion chromatography after the washing treatment were performed using leaves of white birch collected from low part of the tree crown and the top of the tree in Sapporo City, Hokkaido, northern Japan. Each of collected leaves was divided into two parts according to the treatment performed: leaf surface (adaxial side) was 1) untreated, and 2) washed with deionized water with a pipette. In untreated samples, many particles of various shapes, including soil particles and organic debris, were deposited on the surface. Particles containing S were found on the surface of samples collected from only low part of the tree crown. After the washing treatment, SEM-EDX analysis revealed that soil particles and particles containing S had been washed off with water, although some particles such as soil particles and organic debris still remained on the leaf surface. The major anion such as $SO{_4}^{2-}$ was detected in wash water of all samples, although the peak of S in X-ray spectra was not detected from samples collected at top of the tree. The combination of SEM-EDX analysis with wash water analysis indicated that $SO{_4}^{2-}$ was deposited on the leaf surface in dissolved state and/or in state of submicron particles. These results suggested that fog water could remove soil particles and particles containing S and $SO{_4}^{2-}$ from the leaf surfaces, but not all particles. There was no difference in sampling position in the tree crown. Our study suggested that combination with SEM-EDX analysis and wash water analysis would be effective for investigation of the behavior of particles on the leaf surface against fog water.

• Applied Chemistry for Engineering
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• v.16 no.6
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• pp.815-821
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• 2005

Three major commercially available organic chemical admixtures are modified lignosulfonates (LS), sulfonated naphthalene-formaldehyde resins (SNF) and sulfonated melamine-formaldehyde (SMF). In this study, various sulfonated melamine-formaldehyde (SMF) superplasticizers were synthesized via four synthetic steps including hydroxymethylation (Step 1), sulfonation (Step 2), polymerization (Step 3) and neutralization and stabilization (Step 4). In this synthesis, mole ratio of melamine to formaline and the amount of acid catalyst used were varied. The obtained SMF superplasticizers were applied to cement paste and mortar and their physical properties including workability, slump loss, compressive strength were investigated. Also their hydrate shapes were investigated by examining SEM images of the cured paste. It was found that the fluidity properties of cement were significantly influenced by the structure of SMF condensates.

• Bulletin of the Korean Chemical Society
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• v.33 no.10
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• pp.3397-3406
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• 2012

Three types of spherulitic morphologies have been investigated in dual substrate mode of Belousov-Zhabotinsky (BZ) type reaction system. Prior to growth of spherulites, three distinct patterning behaviors have been observed sequentially during the reaction process. Initial and the early-phase of reaction showed the emergence of concentric ring-like wave patterns. A colloidal-state of reaction consists of numerous fine solid particles, which forms primarily some nucleation centers of dendritic characters. The nucleation centers were found to grow in sizes and shapes with the progress of reaction. It leads to growth of dendritic-like spherulitic crystal patterns. The resultant spherulites showed transitions in their morphologies, including sea-weeds and rhythmic spherulitic crystal patterns, by the effects substituted organic substrate and in the higher concentration of bromate-initiator respectively. The branching mechanism and crystal ordering of spherulitic textures were studied with help of optical microscope (OPM) and scanning electron microscope (SEM). Characteristics of crystal phases were also evaluated using X-ray diffraction (XRD) and differential thermal analysis (DTA). Results indicated that the compositions of reactants and crystal orderings were interrelated with morphological transitions of spherulites as illustrated and described.