• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.429.2-429.2
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• 2014

ZnO nanowire is known as synthesizable and good mechanical properties. And, stimuli-responsive polymer is widely used in the application of tunable sensing device. So, we combined these characteristics to make precise tunable sensing devise. In this work, we investigate the dependence of ZnO nanowire alignment and morphology on si substrate using nanosphere template with various conditions via hydrothermal process. Also, pH-temperature dependant tuning ability of nanostructure was studied. The brief experimental scheme is as follow. First, Zno seed layer was coated on a si wafer ($20{\times}20mm$) by spin coater. And then $1.15{\mu}m$ sized close-packed PS nanospheres were formed on a cleaned si substrate by using gas-liquid-solid interfacial self-assembly method. After that, zinc oxide nanowires were synthesized using hydrothermal method. Before the wire growth, to specify the growth site, heat treatment was performed. Finally, NIPAM(N-Isopropylacrylamide) was coated onto as-fabricated nanostructure and irradiated by UV light to form the PNIPAM network. The morphology, structures and optical properties are investigated by FE-SEM(Field Emission Scanning electron Microscopy), XRD(X-ray diffraction), OM(Optical microscopy), and WCA(water contact angle).

• Korean Journal of Plant Taxonomy
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• v.40 no.1
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• pp.27-42
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• 2010

This study was intended to investigate the capitulum morphology and to evaluate its taxonomic importance within the 23 taxa of Korean Artemisia L. The Korean Artemisia was classified into sterile subg. Dracunculus and fertile subg. Artemisia by the fertility of the disk florets, which is the traditional diagnostic character of subgenera. There are sections in subg. Artemisia: sect. Absinthium with a densely, sparsely hairy receptacle, and sect. Abrotanum and sect. Artemisia with a glabrous receptacle. However, A. fukudo and A. sacrorum belonging to sect. Abrotanum, and A. viridissima belonging to sect. Artemisia were observed to have sparsely hairy receptacles. Therefore, the presence of hair on a receptacle, which is now regarded as a key character distinguishing sections, has to be reevaluated. The whole shape and size of the capitulum, the characteristic of the stigma apex, the hair on the involucral bract, and the shape of the central or peripheral floret are thought to be the most valuable characters to consider in recognizing species.

• Korean Journal of Weed Science
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• v.8 no.1
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• pp.9-14
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• 1988

Three varieties of Echinochloa crus-galli (L.) Beauv. and five collections different in gross morphology from the E. crus-galli species were obtained in a lowland rice field located in Jukjeol-Ri, Soyang-Myeon, Wanju-Kun, Jeonbug to compare the ecological and physiological characteristics. There were great variations in seed dormancy, relative growth rates, days required to panicle emergence and panicle morphology among the collections. On the basis of the cluster analysis using the different characteristics, the collections were divided into three groups; E. crus-galli var. frumentaceae and its two ecotypcs, E. crus-galli var. echinata and its two ecotypes, and E crus-galli var. crus-galli and its one ecotype. There were differential responses in percent germination and post-germination growth of the collections to butachlor (2-chloro-2', 6'-diethyl-N-butoxymethyl acetanilide).

• Korean Journal of Materials Research
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• v.21 no.12
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• pp.660-665
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• 2011

1-D ZnO nanowires have been attractive for their peculiar properties and easy growth at relatively low temperature. The length, diameter, and density of ZnO nanowires were determined by the several synthetic parameters, such as PEI concentration, growth time, temperature, and zinc salt concentration. The ZnO nanowires were grown on the <001> oriented seed layer using the hydrothermal process with zinc nitrate and HMTA (hexamethylenetetramine) and their structure and optical properties were characterized. The morphology, length and diameter of the nanowires were strongly affected by the relative and/or absolute concentration of $Zn^{2+}$ and $OH^{-1}$ and the hydrothermal temperature. When the concentrations of the zinc nitrate HMTA were the same as 0.015 M, the length and diameter of the nanowires were $1.97{\mu}m$ and $0.07{\mu}m$, respectively, and the aspect ratio was 28.1 with the preferred orientation along the <001> direction. XRD and TEM results showed a high crystallinity of the ZnO nanowires. Optical measurement revealed that ZnO nanowires emitted intensive stimulated UV at 376 nm without showing visible emission related to oxygen defects.

• International Journal of Industrial Entomology and Biomaterials
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• v.37 no.2
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• pp.105-108
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• 2018

Recently matured silkworm powder was developed by RDA. In this study, the effect of pulverizing method on the particle size of matured silkworm powder was examined. FESEM was performed to observe the morphology and to measure the particle size of silkworm powder. Particle morphology of air-jet mill pulverized powder was round and smooth, however, those of roller-mill and hammer-mill pulverized mature silkworm was more harsh and square. Particle size was varied with pulverizing technique as follows; $1.1{\mu}m$ (air-jet mill), $10{\mu}m$ (roller mill), and $120{\mu}m$ (hammer mill), respectively. A proximate analysis results of air-jet mill powder showed that crude protein, crude lipid, crude fiber, and ash was 73%, 12%, 1.95%, and 3.4%, respectively. According to our results, air-jet mell technique might be used to make a tiny matured silkworm powder.

• Journal of Korean Society of Forest Science
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• v.86 no.3
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• pp.378-390
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• 1997

Ten total populations of Korean fir (Abies koreana Wilson) and Manshurian fir [A. nephrolepis (Traut.) Maxim.] were sampled from south Korea to investigate patterns of intraspecific variation in these species and to evaluate a recognition of the two species. Principal components analysis and cluster analysis were performed both on seed-cone data and on needle morphology data. The characters that contributed most to the separation between A. koreana and A. nephrolepis along three principal components axis were leaf width, length of seed, width of seed wing, length of seed wing, cone width, width of scale, and length of bract tip, but these characters were not diagnostic because of overlap in reality. Therefore, all these characters were not reliable in distinguishing these two taxa including bract position (exerted and recurved vs. exerted and straight). The individuals of A. koreana from Mt. Chi-ri appeared quite unique probably on account of its larger cone size and longer scale tip, while those from Mt. Hal-la of A. koreana were generally distinct from others in terms of their larger seed and seed wing and longer scale width. The Mt. Duk-yu specimens of A. korecana appeared somewhat smaller but more data were needed due to the small sampling size. Generally, the gradual clinal geographic trends made evident by the position of resin ducts in leaves of A. koreana can be detected. The southern populations, Mt. Hal-la (an insular population) were generally distinct from the northern populations (Mt. Chi-ri, Mt. Ga-ya and Mt. Duk-yu) in terms of their position of resin duct (medial, within mesophyll vs marginal, close to epidermis : 100% vs 75 or 50%). Although no sharp boundary separating these two species could be detected based on cone and needle morphology, the observed clinal pattern was distinct in northern populations of A. koreana and southern population of A. nephrnlepis. In a preceding study of the flavonoids variation of 20 species in eastern Asia, flavanone (5-deoxyflavanone) was found to be characteristic of A. faxoniana Rehder et Wilson, A. georgei Orr of China and A. koreana of Korea. A. faxoniana, which is assumed to be primitive species, has position of resin duct relative to both the medial and the marginal, while A. georgei and A. koreana are identified by marginal position of resin duct. With respect of foliar flavonoids chemistry, A. koreana was distinct from A. nephrolepis : the southmost samples (Mt. Hal-la and Mt. Chi-ri) contained additional flavonoids derivatives (mainly flavanone) that were not found in the northmost samples of A. nephrolepis except a few individuals from Mts. Seo-rak and Tae-bak populations of Kwang-won province. The presence of A. koreana type flavonoids in two Chinese species suggested that position of resin duct may be a phyletic character. Abies koreana including two Chinese taxa, exhibited the most elaborate and specialized flavonoids profile within the Abies in eastern Asia. Contrary to our initial expectations, the apparent intermediates between A. nephrolepis and A. koreana in Duk-yu and Ga-ya mountains were found. The pattern of variation on position of resin duct and flavonoids chemistry in these populations of A. kareana suggested that genetic interchange or natural hybridization had occurred between these two species. The evidence needed to resolve the status of this taxon is still inconclusive in our opinion until intermediate individuals from Mts. Duk-yu and Ga-ya show indication of hybridization between the two species.

• Korean Journal of Plant Taxonomy
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• v.37 no.4
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• pp.431-446
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• 2007

The purpose of this study is to review the taxonomical position of Phytolacca insularis Nakai based on morphological characters and ITS sequences. Phytolacca insularis was similar to P. acinosa in the stem shape, inflorescence, apocarpous, eight pistils, eight stamens, pink anther, and eight fruits. But the unique difference between P. insularis and P. acinosa was leaf size and pistil color. Phytolaccri insularis and P. acinosa have a similar sculpturing patterns as an foveolate and microscabrate in pollen, but they differed from P. americana in having a bigger foveolae size in sculpture pattern. Phytolacca insularis and P. acinosa were similar in the seed size but different from P. americana by having a small size of seed. The seed surface of P. insularis and P. acinosa was similar with a irregularly undulate shape, but its feature of P. americana differed in having the reticulate shape. Phytolacc a insularis had identical ITS sequences with P. acinosa. Phytolacca insularis and P. acinosa have a close relationship in the morphological characters and ITS sequences. The examinations of morphology and ITS sequences suggest that P. insularis be a form of P. acinosa although it has been formerly treated as a distinct species.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1239-1244
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• 2003

Microcapsules were prepared by coacervation method using acetone/liquid paraffin system to control the ripening of kimchi. Eudragit E100, which was soluble at below pH 5.0 in aqueous solution, was used to make microcapsules to be sensitive to acidity of kimchi. The microcapsules with Eudragit E100 containing grapefruit seed extract (GFSE) showed the highest yield of 92.13%, the size of microcapsules was decreasing as increasing the amount of aluminium stearate, a dispersing agent. Morphology of the microcapsules determined by scanning electron microscopy showed spherical forms. GFSE, encapsulated antimicrobial agents, was quickly released at acidic buffer (pH 4,5,6) within 1 storage day. However, 70% of encapsulated GFSE in Eudragit E100 microcapsules was continuously released at pH 7 till 3 days, and it was sustained till 9 days. Characteristics of kimchi containing microcapsules of GFSE were analysed with ripening period. Decease of pH in kimchi was retarded with the added GFSE microcapsules till 2 days of fermentation, but GFSE did not affect pH in kimchi after 3 days. Total numbers of microorganisms and lactic acid microorganisms in kimchi were decreased with increasing the amount of the added GFSE microcapsules, however, the effect of controlled released GFSE from pH sensitive Eudragit E100 microcapsules was hard to detect. These results suggest the possibility of pH sensitive microcapsules for high qualify of kimchi.

• Journal of the Korean Vacuum Society
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• v.19 no.2
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• pp.128-133
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• 2010

ZnO:Al films were deposited by DC-pulsed magnetron sputtering using a two-step process involving the control of the oxygen pressure. The seed layers were prepared with various Ar to oxygen flow ratios and the bulk layers were deposited under pure Ar. As the oxygen pressure during the deposition of the seed layer increased, the crystallinity and degree of (002) texturing increased. The resistivity gradually decreased with increasing crystallinity from $4.7\times10^4\Omega{\cdot}cm$ (no seed) to $3.7\times10^4\Omega{\cdot}cm$ (Ar/$O_2$ = 9/1). The etched surface showed a crater-like structure and an abrupt morphology change appeared as the crystallinity was increased. The sample deposited at an Ar/$O_2$ flow ratio of 9/1 showed a very high haze value of 88% at 500 nm, which was explained by the large feature size of the craters, as shown in the AFM image.

• Journal of Wetlands Research
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• v.17 no.2
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• pp.139-145
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• 2015

The purpose of this study is to describe and compare the morphological characteristics of seeds of 12 taxa of Araliaceae, and to evaluate their possible use for taxonomic considerations. For light microscope observations and measurements, the seeds were observed using Image Analyzing System. The observations were made on twenty randomly selected seeds of each species. Obtained data were statistically processed using analysis of variance. Principal Components Analysis indicated four groups of characters, the genera Aralia, Eleutherococcus, Panax and the others, which explained 65.47% of the total variation. As a results of Cluster Analysis using the eleven variables, 12 species of Araliaceae were also discriminated into four groups. Eleutherococcus senticosus and E. gracilistylus were closely related, which is well supported by the results from recent molecular studies. Also, the genera Dendropanax and Eleutherococcus were closely related in terms of seed characters.