• Proceedings of the Plant Resources Society of Korea Conference
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• 2002.11b
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• pp.6-7
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• 2002

The goal of this research was to develop the effectiveness of in vitro culture method for A. formosanus and study the environment in vitro conditions affecting on growth. The first series of experiments were examined to investigate the response of three different basal media, MS (Murashige and Skoog, 1962), Knudson (KC; Knudson, 1946) and modified hyponex on growth and multiplication during in vitro culture. Multiple shoot proliferation was induced in shoot tip explants on Hyponex (H3) media supplemented with BA (1 mg1$^{-1}$) or TDZ (1-2 mg1$^{-1}$). Addition of activated charcoal (1%) to the TDZ containing medium promoted rapid shoot tip proliferation (11.1 shoots per explant) but the same medium had an opposite effect resulting in poor proliferation in the nodal explants. However, the regenerated shoots had slow growth rate and failed to elongate. This problem was overcome by transferring the shoot clumps to a hormone free H3 media supplemented with 2% sucrose and 0.5% activated charcoal. Using bioreactor culture for scaling up was also shown the best way for multiple shoot induction and growth of this plant.(중략)

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.156-156
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• 2017

Plants are grown under constitutive changing of environmental conditions and response to external conditions at both protein and transcription level. The effects of heat on plant growth are broad and influence the yield directly. Heat stresses could be classified depend on intensity and duration. Fundamental changes of growth condition by climate change maybe or maybe not classified as a stress on plant growth. The effects of a short and unanticipated impact of elevated heat on plant could be different with those of under longer extension of ambient heat. To examine differently expressed gene sets by ambient heat stress of soybean, we grow the soybean in normal condition for three weeks. After that, soybean plants move to growth chamber. The temperature of growth chamber increase up to $9^{\circ}C$ for four days. We have extracted mRNA and micro RNA every 24 hours and carried RNA sequence analysis. We found major metabolic pathways affected by ambient heat stress. Mainly carbon metabolism, translation machinery and amino acid synthesis are affected. We discussed the expression patterns of genes of heat sensing and hormone responses.

• Transactions of Materials Processing
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• v.20 no.7
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• pp.491-497
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• 2011

This work describes a method for determining material parameters included in recrystallization and grain growth models of metallic materials. The focus is on the recrystallization and grain growth models of Ni-Fe based superalloy, Alloy 718. High temperature compression test data at different strain, strain rate and temperature conditions were chosen to determine the material parameters of the model. The critical strain and dynamically recrystallized grain size and fraction at various process conditions were generated from the microstructural analysis and strain-stress relationships of the compression tests. Also, isothermal heat treatments were utilized to fit the material constants included in the grain growth model. Verification of the determined material parameters is carried out by comparing the average grain size data obtained from other compression tests of the Alloy 718 specimens with the initial grain size of $59.5{\mu}m$.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.1 no.2
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• pp.34-45
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• 1991

The fundamental conditions for growing $r-6Bi_2O_3{\cdot}GeO_2$ (BGO) single crystal plates by EFG (Edge -defined Film-fed Growth) method, were investigated and the characterization, quality test were carried out for obtained BGO single crystal plates. The optimum growing conditions determined in this study were as follows: ${\cdot}$ temperature gradient: 22^{\circ}C/cm

• Ecology and Resilient Infrastructure
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• v.5 no.2
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• pp.82-87
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• 2018

Proliferation of algae on the surface of concrete or mortar in aquatic habitat has a negative impact on maintenance of concrete-based structures. Growth of algae may decrease stability of structure by bio-deterioration. In this study, we developed a functional mortar for restraining bio-deterioration by using $Cu^{2+}$ ion. The mortar contains soluble glass beads made of $Cu^{2+}$ ion, which can dissolve into water slowly. Mortars prepared with different ratio of glass beads (0, 2, 5, 10, and 15%) were placed in a culture medium with algae and incubated over a month period. Water chemistry, chlorophyll-a, and extracellular enzyme activities were measured. The incubation was conducted in both freshwater and seawater conditions, to assess applicability to both aquatic conditions. Overall, mortar with Cu glass exhibited lower chlorophyll-a content, suggesting that the functional mortar reduced algal growth. DOC concentration increased because debris of dead algae increased. Cu glass also decreased phosphatase activity, which is involved in the regeneration of inorganic P from organic moieties. Since, P is often a limiting nutrient for algal production, algal growth may be inhibited. Activities of ${\beta}$-glucosidase and N-acetylglucosaminidase were not significantly affected because carbon and nitrogen mineralization may not be influenced by the Cu glass beads. Our study suggests that functional mortar with Cu glass beads may reduce the growth of algae on the surface, while it has little environmental impact.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.250-250
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• 2011

Zinc oxide (ZnO) structures have great potential in many applications. Currently, the most commonly used method to grow ZnO nanostructres are the vapor transport method (VPT). The morphology of the ZnO structures largely related to the growth conditions, including growth temperature, distance between the substrate and source, and gas ambient. Previously ZnO nanosturecutres with high crystallinity were obtained at the growth temperature of 800$^{\circ}C$, in the argon and oxygen gas ambient. In this study, we report the properties of the ZnO nanostructures, which were synthesized on Au-catalyzed Si substrate by VPT, using a mixture of ZnO and graphite powders as source material under the different condition, including gas ratio of argon/oxygen and distance between substrate and source at the growth temperature of 800$^{\circ}C$. The structural and optical properties of the ZnO nanostructures were investigated by field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and photoluminescence (PL).

• Microbiology and Biotechnology Letters
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• v.33 no.3
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• pp.222-225
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• 2005

Stimulatory effects of near infra-red (NIR) rays radiation have been studied within the limits of photosynthesis, phototaxis, and photodermatology. While most of these studies have been done by direct NIR radiation, we investigated the effects of the NIR rays-treated materials on microbial growth. NIR in wavelength of 1,400${\~}$1,700 nm was applied for different kind of materials. Under fast growing conditions in rich media, materials treated with the NIR rays or not did not show any differences in growth of microorganisms. However, under slow growing conditions in minimal media, data showed that NIR rays-treated cloths and hygienic bands affect negatively on the growth of bacteria (Salmonella enteritidis) and fungi (Candida albicans). In addition, it was estimated that the effect of NIR rays on bacterial growth is kept going on S. enteritidis.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1571-1573
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• 2003

Diamond films including nanocystalline and graphite phase are grown by microwave plasma chemical vapor deposition using $N_2$ additives and negative substrate bias at growth step. The microstructure of the films is controlled by changing $N_2$ gas ratio and negative bias. Defects and grain boundaries between diamond and graphite are proposed to be crucial factors for forming the conducting path of electron emissions. The effect of growth parameters on the film microstructure are investigated by Raman spectroscopy and scanning electron microscopy(SEM). Electron emission characteristics are also examined in terms of the film growth conditions.

• ALGAE
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• v.28 no.2
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• pp.203-211
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• 2013

Dunaliella salina and Dunaliella bardawil are well known for carotenogenesis, the overproduction of carotenoids, under stress conditions. The effect of high light (HL) and low light (LL) on the growth, morphology, photosynthetic efficiency, and the ${\beta}$-carotene and zeaxanthin production of D. salina CCAP 19/18 and D. bardawil was investigated and compared. Both strains showed similar growth kinetics under LL growth condition, but D. salina CCAP 19/18 was faster. As the light intensity increased, D. salina CCAP 19/18 cells were elongated and D. bardawil cells became larger. Both strains showed decrease of the maximum quantum yield of PSII ($F_v/F_m$) and election transport rate (ETR) under HL growth condition and D. salina CCAP 19/18 was less liable to the light stress. Both strains had about 1.8 and 5 times difference in the $O_2$ evolution rate at LL and HL conditions, respectively. The ${\beta}$-carotene and zeaxanthin production were increased as the light intensity increased in both strains. D. bardawil was more sensitive to light intensity than D. salina CCAP 19/18. The possible application of D. salina CCAP 19/18 as a carotenogenic strain will be discussed.

• Journal of Marine Bioscience and Biotechnology
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• v.12 no.2
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• pp.115-122
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• 2020

Eisenia bicyclis, a perennial macroalga is a primary producer of in the ocean, It has been identified as a key species that plays a vital role in maintaining the ecosystem stability. Also, it is an important target in marine afforestation projects and useful marine organisms. In addition, E. bicyclis is used as a health food for humans. This study investigated the effect of water temperature, light (photon irradiance), and duration of light (photoperiod) on the growth of gametophytes and young sporophytes of E. bicyclis. The germination and growth of the zoospores of E. bicyclis were examined at five temperatures (5℃, 10℃, 15℃, 20℃ and 25℃), four intensities of photon irradiance (10, 20, 40, and 80 μmol m-2s-1), and photoperiods (14:10 and 10:14 light/dark cycles). The zoospores released from mature plant germinated into the gametophytes under all experimental conditions. The gametophytes were able to grow at water temperature 5℃-25℃ and mature at 10℃-20℃. The optimal range of water temperature for the maturation of the gametophyte was 15℃-20℃. At 25℃, E. bicyclis gametophytes grew rapidly but did not mature. The optimal culture conditions for the growth of young sporophytes grew slowly in low temperature and photon irradiances.