• 인간식물환경학회지
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• 제22권6호
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• pp.551-561
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• 2019

This study was conducted to find out differences in the removal efficiency of particulate matter (PM) depending on the type of plants and the morphological characteristics of leaves. A total of 12 plants were used, with three plants selected for each type of leaves (big leaf, small leaf, compound leaf, needle leaf). We measured the removed amount of PM10 and PM2.5, the structure of the abaxial leaf surface, and the weight of the wax layer of each plant. Plants with the high removal efficiency of PM included Pachira aquatica Aubl., Ardisia crenata, and Dieffenbachia 'Marianne', and plants with the low removal efficiency included Nandina domestica Thunb, Schefflera arboricola, and Quercus dentata. The abaxial leaf surface having a high removal efficiency of PM had many large wrinkles, and the abaxial leaf surface having a medium removal efficiency was flat and smooth. On the other hand, there were many fine hairs on the abaxial leaf surface with a low removal efficiency. According to the plant leaf type, the PM10 removal efficiency of plants with needle leaves was about three times higher than that of other plants. In particular, the wax layer of conifers weighed 6-24 times higher than those of other plants. The stomata of conifers were evenly distributed on the adaxial and abaxial leaf surfaces; however, the stomata of Sciadopitys verticillata appeared in the form of papillae unlike general stomata. Therefore, the removal efficiency of PM varied depending on the macro-, and micro-morphological characteristics of plant leaves such as the structure of the abaxial leaf surface, and the weight of the wax layer. Based on this research, selecting plants that are effective in reducing PM in consideration of the plant type and leaf characteristics will improve indoor air quality and decrease exposure of PM to human body.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2009년도 추계학술발표대회
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• pp.33.1-33.1
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• 2009

To date, nanostructured tungsten oxides with a variety of stoichiometries, such as WO3, WO2.9, W18O49, and WO2, have been prepared, because they are promising candidates for applications such as gas sensors, photocatalysts, electrochromic devices, and field emission devices. Among them, W18O49 and WO2 have been widely studied due to their outstanding chemical sensing, catalytic, and electron emissive properties. Here we report, for the first time, a one-pot solution-phase route to synthesizing a novel composite hierarchical hollow structure without adding catalysts, surfactants, or templates. The products, consisting of a WO2 hollow core sphere surrounded by a W18O49 nanorod shell (yielding a sea urchin-like structure), were generated as discrete structures via Ostwald ripening. To our knowledge, this type of composite hierarchical core/shell structure has not been reported previously. The morphological evolution and the detailed growth mechanism were carefully studied. We also demonstrate that the size of the hollow urchins is readily tunable by controlling the reactant concentrations.Interestingly, although bulk tungsten oxides are weakly paramagnetic or diamagnetic, the as-prepared products show unusual ferromagnetic behavior atroom temperature. The urchin structures also show a very high Brunauer-Emmet-Teller (BET) surface area, suggesting that they may potentially be applied to chemical sensor or effective catalyst technologies.

• Fibers and Polymers
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• 제4권1호
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• pp.15-19
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• 2003

The self-assembly of asymmetric ABC triblock copolymers in the ordered structure is investigated using an isothermal-isobaric molecular dynamics simulation. Unlike symmetric A BC triblock copolymers, more fascinating mophologies are observed in asymmetric ones because of a larger difference of incompatibility between the components. Various modes of self-assembly in assymmetric ABC triblock copolymers are also observed depending on the block composition. When the composition of block A Is changed from 0.125: to 0.25 at the same $f_B$ : 0.25, the morphological transition from the “cylinder in cylinder” to “cylinders at cylinder” structure is observed in the simulation. In the case of ABC triblocks with $f_B$=0.5, a lamellar-type structure is changed to a cylinder-type structure with increasing the length of block A. When the midblock length increases further to $f_B$=0.625, the “spheres on cylinder” structure is observed in both the $A_{10}$$B_{50}$$C_{20}$ and $A_{20}$$B_{50}$$C_{10}$ triblocks. From these results, the phase diagram of ABC triblock copolymers can be constructed.

• Applied Microscopy
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• 제52권
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• pp.6.1-6.5
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• 2022

We examined the morphology of the fertilized egg and the fine structure of fertilized egg envelopes of Poropanchax normani belonging to the family Poeciliidae, also known as Norman's lampeye using light and electron microscopes. The fertilized eggs with narrow perivitelline space were found to be spherical and demersal, additionally containing small oil droplets in the vitelline membrane. Further, a bundle of adhesive filaments was observed to be present on one side of the fertilized egg. These filaments possessed remarkably high elasticity and were approximately 1-3mm in length. The size of the fertilized egg was determined to be about 1.49 ± 0.07mm (n=30). The outer surface appeared smooth, and adhesive filaments originating at different location of the surface of the envelope were found to be distributed around the egg envelope and were joined together to form a single long bundle in scanning electron microscopic observation. A peak-like structure formed of several straight wrinkles was observed around the micropyle. However, the complete structure of the micropyle could not be studied due to the depth at which it was located. Additionally, the total thickness of the egg envelope was ascertained to be approximately12.5-14.5㎛. The egg envelope consisted of two distinct layers, an outer electron dense layer and an inner lamellar layer, further consisting of 10 sublayers of varying thicknesses. Collectively, it was observed that the morphological characteristics of the fertilized egg, fine structures surrounding the micropyle, outer surface, adhesive structure consisting adhesive filaments, and sections of fertilized egg envelope displayed species specificity.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1999년도 봄 학술발표회 논문집
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• pp.249-252
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• 1999

• Mycobiology
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• 제32권1호
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• pp.54-56
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• 2004

During the study of mushroom flora in Hongneung Arboretum, Ileodictyon gracile was confirmed as new to Korea and described based on morphological and microscopic characteristics in here. This species has subhypogeous, clathrate structure, and obovoid spores. The clathrate structures have $4{\sim}12$ polygonal meshes.

• 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
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• 한국정보과학회언어공학연구회 1998년도 제10회 한글 및 한국어 정보처리 학술대회
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• pp.49-55
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• 1998

분단 이후 북한은 우리와는 다른 언어정책을 추진해 왔고, 그 결과로 지금은 남북한 언어 정책에서 많은 차이를 드러내게 되었다. 본 논문은 북한 문화어 형태소 분석 시스템(NKMA)의 구축을 위한 어절 구조를 제시한다. 북한 문화어의 형태소 분절 및 분석을 위해 사용된 어절 구조는 대체로 말토막 단위와 일치하므로, 음성언어의 인식을 위한 분절 방법에 응용될 수도 있으리라 기대한다.

• Journal of Species Research
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• 제6권spc호
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• pp.135-147
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• 2017

Seven new species in two genera, Sarcotragus and Bergquistia (Demospongiae: Dictyoceratida: Irciniidae), are described from Jeju Island, Korea. The separation of the two genera was made on basis of morphological evidence in skeletal structure, especially fasciculation of primary fibres and filament thickness. Two new species in the genus Sarcotragus and five new species in the genus Bergquistia are compared with other reported species.

• Journal of Species Research
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• 제6권spc호
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• pp.94-109
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• 2017

Eleven new species of two genera, Psammocinia and Ircinia (Demospongiae: Dictyoceratida: Irciniidae) are described from Gageo Island, Ulleung Island and Jeju Island, South Korea. The separation of these two genera was made on basis of morphological evidence, especially skeletal structure with foreign debris. Six new species of Psammocinia and five new species of Ircinia were added to known fauna. All skeletal fibres are very irregular.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.516-519
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• 2003

We modified the molecular structure of urethane acrylate oligomer by varying raw materials. Also fluorination of the host polymer matrices has been found to influence the morphological and the electrooptical properties of the resulting HPDLC grating. The incorporation of fluorinated monomers in HPDLC formulation enhance the LC phase separation and improved elctro-optical properties.