• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.4
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• pp.20-25
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• 2020

As nanoscience and nanotechnology advance, techniques for selective pattern growth have attracted significant attention. Silica nanoparticles (NPs) are used as a promising nanomaterials for bio-labeling, bio-imaging, and bio-sensing. In this study, silica NPs were synthesized by a sol-gel process using a modified Stöber method. In addition, the selective pattern growth of silica NPs was achieved by the surface functionalization of the substrate using a micro-contact printing technique of a hydrophobic treatment. The particle size of the as-synthesized silica NPs and morphology of selective pattern growth of silica NPs were characterized by FE-SEM. The contact angle by surface functionalization of the substrate was investigated using a contact angle analyzer. As a result, silica NPs were not observed on the hydrophobic surface of the OTS solution treatment, which was coated by spin coating. In contrast, the silica NPs were well coated on the hydrophilic surface after the KOH solution treatment. FE-SEM confirmed the selective pattern growth of silica NPs on a hydrophilic surface, which was functionalized using the micro-contact printing technique. If the characteristics of the selective pattern growth of silica NPs can be applied to dye-doped silica NPs, they will find applications in the bio imaging, and bio sensing fields.

• Proceedings of the Korean Vacuum Society Conference
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• 2003.02a
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• pp.92-92
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• 2003

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.05a
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• pp.24.2-24.2
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• 2009

Nanostuctures such as nanodot and nanowire have been extensively studied as building blocks for nanoscale devices. However, the direct growth of the nanostuctures at the desired position is one of the most important requirements for realization of the practical devices with high integrity. Self-assembled nanotemplate is one of viable methods to produce highly-ordered nanostructures because it exhibits the highly ordered nanometer-sized pattern without resorting to lithography techniques. And selective epitaxial growth (SEG) can be a proper method for nanostructure fabrication because selective growth on the patterned openings obtained from nanotemplate can be a proper direction to achieve high level of control and reproducibility of nanostructucture fabrication. Especially, SiGe has led to the development of semiconductor devices in which the band structure is varied by the composition and strain distribution, and nanostructures of SiGe has represented new class of devices such nanowire metal-oxide-semiconductor field-effect transistors and photovoltaics. So, in this study, various shaped SiGe nanostructures were selectively grown on Si substrate through ultrahigh vacuum chemical vapor deposition (UHV-CVD) of SiGe on the hexagonally arranged Si openings obtained using nanotemplates. We adopted two types of nanotemplates in this study; anodic aluminum oxide (AAO) and diblock copolymer of PS-b-PMMA. Well ordered and various shaped nanostructure of SiGe, nanodots and nanowire, were fabricated on Si openings by combining SEG of SiGe to self-assembled nanotemplates. Nanostructure fabrication method adopted in this study will open up the easy way to produce the integrated nanoelectronic device arrays using the well ordered nano-building blocks obtained from the combination of SEG and self-assembled nanotemplates.

• The Korean Journal of Food & Health Convergence
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• v.3 no.1
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• pp.1-7
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• 2017

The study has made theoretical system by thesis journals at home and abroad, material of the Association of Convenience Store Industry of Korea, materials of Statistics Korea and reference books. First, the study examined convenience store's brand image, cognized value, quality level, reliability upon brand, structural relation of purchasing intention, and designed models and theses. Second, the first questionnaire consisted of test items of precedent study, and inspected in advance to inspect reliability and appropriateness, and made correction and supplemented problems. Third, SPSS and AMOS statistics were used to conduct empirical analysis and to find out conclusion and implications. In this study, the subject was consumers who visited local convenience stores such as GS25, Seven Eleven and CU last 3 months to buy PB food. Consumers' consumption pattern and culture made change to be reasonable and practical owing to aging society, nuclear family, women's entering into the society, one person household consumer, and convenient and prompt buying to make different consumption pattern and to make change of commodity distribution pattern. Convenience store took action against change of the trend to expand business area by new distribution channels to get another growth source. Private brand (PB) food that was distributor's brand was expanded. The PB product has been competitiveness of food service industry.

• Korean Journal of Materials Research
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• v.9 no.3
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• pp.257-262
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• 1999

The selective area growth of GaN by metal organic chemical vapor deposition has been carried out on GaN/ sapphire substrate using $SiO_2$ mask. We investgated the effect of growth parameters such as flow rate of $NH_3$(500­~1300sccm) and the growth temperature(TEX>$950~1060^{\circ}C$) on the growth selectivity and characteristics of GaN using the Scanning Electron Microscopy(SEM). The selectivity of GaN improved as flow rate of NH, and growth temperature in­creased. But the grown GaN shapes on the substrate windows was independent of the flow rate of $NH_3$. On the pattern shapes such as circle, stripe, and radiational pattern(rotate the stripe pattern by $30^{\circ}, 45^{\circ}$), we observed the hexagonal pyramid, the lateral over growth on the mask layer, and the difference of the lateral growth rate depending on growth condition.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.463-472
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• 2014

Ion imbalance in recycled nutrient solutions is caused by selective ion uptake of plants, which occurs at different rates in different growth stages. The objectives of this study were to investigate the ion balances in both recycled nutrient solutions and rockwool media using different renewal patterns for the nutrient solutions, and to analyze the subsequent effects on uptake of water and nutrients. Over 12 weeks of paprika cultivation, two different renewal patterns (week units) of 6-4-2 and 8-2-2 weeks were compared with a constant renewal pattern of 4-4-4 weeks (control). The nutrient solution in the reservoir tank was constantly maintained at EC $2.5dS{\cdot}m^{-1}$ and pH 5.5-6.5. The changes in the ion balance with the 4-4-4 week pattern were smaller than those with the other treatments. In the early growth stage, however, the ion balances similarly changed among all treatments. Greater changes were subsequently observed for the 6-4-2 week pattern. Although fruit yield and shoot fresh weight of paprika were the lowest with 6-4-2 renewal pattern, no significant differences were observed. Our results indicate that renewal intervals can be extended in consideration of growth stage for more efficient and practical operations in closed soilless cultures.

• Journal of Integrative Natural Science
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• v.4 no.4
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• pp.311-314
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• 2011

Application of self-assembled monolayers (SAMs) to the fabrication of organic thin film transistor has been recently reported very often since it can help to provide ohmic contact between films as well as to form simple and effective electrode pattern. Accordingly, quality of these ultra-thin films is becoming more imperative. In this study, in order to manufacture a high quality SAM pattern, a hydrophobic alkylsilane monolayer and a hydrophilic aminosilane monolayer were selectively coated on $SiO_2$ surface through the consecutive procedures of a micro-contact printing (${\mu}CP$) and dip-coating methods under extremely dry condition. On a SAM pattern cleaned with SC1 solution immediately after ${\mu}CP$, poly(3,4-ethylenedioxythiophene) (PEDOT) source and drain electrode array were very selectively and nicely vapour phase polymerized. On the other side, on a SC1-untreated SAM pattern, PEDOT array was very poorly polymerized. It strongly suggests that the SC1 cleaning process effectively removes unwanted contaminants on SAM pattern, thereby resulting in very selective growth of PEDOT electrode pattern.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.30 no.4
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• pp.333-344
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• 2008

The objectives of this study was to explore the growth pattern of the oral squamous cell carcinoma when overexpressed COX was inhibited, explore the pathway that COX inhibitors suppressed the proliferation of cancer cells, and then hereafter investigate the potential of COX as chemopreventive target for oral squamous cell carcinoma. For confirming the COX-dependent effect and mechanisms on growth of the oral cancer cells, we treated the nonselective NSAID, Mefenamic acid and COX-2 selective inhibitor, Celecoxib in HN4 cell line. And then the cell line was evaluated with MTT assay and growth curve, the production of PGE2, total RNA extraction and RT-PCR analysis, and TEM The results were obtained as follows: 1. After administration of medication, in the result of MTT assay, Celecoxib inoculated group inhibit the cell growth rather than Mefenamic acid inoculated group. 2. The growth curve of cell line showed as time passes by there was a dramatic cell growth in the control group, and gradual growth inhibition was found in medication inoculated group and, in Celecoxib inoculated group there was more inhibition of cell growth. 3. After the administration of medication, Celecoxib tend to inhibit the synthesis of PGE2 more than Mefenamic acid. Mefenamic acid inhibit the synthesis of PGE2 more as the concentration gets high, but Celecoxib inhibited the synthesis of PGE2 even in low concentration. 4. After the administration of medication, the revelation of COX mRNA in cell line, there was a 50% decrease in COX-1, 60% decrease in COX-2 as in $50{\mu}M$ Mefenamic acid, and in Celecoxib $50{\mu}M$ there was not much difference in COX-1 and 90% decrease in COX-2 was found. 5. HN4 cell line showed broken nucleus and tangled cytoskeleton bundles in cytoplasm which meant apoptotic features after the treatment of Celecoxib in TEM view. Depending on the above results, we estimate that the inhibition of the expression of COX-2 cause the growth suppression of the oral squamous cell carcinoma, and it get achieved through pathway of reduced PGE2 production and increased apoptosis. In addition to, because COX-2 selective inhibitor specifically act to COX-2, it is considered that COX-2 selective inhibitor has the adequate potential as chemopreventive agent for oral squamous cell carcinoma.

• Journal of the Korean Ceramic Society
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• v.44 no.4 s.299
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• pp.202-207
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• 2007

High-Quality 1-Dimensional InN single crystalline have been grown by Halide Vapor-Phase Epitaxy on the Au catalyst coated Si substrate using the vapor-liquid-solid growth mechanism. We have been grown 1-dimension InN nanowires having controlled the growth conditions for substrate temperature and gases flow rate. The grown InN nanowire of characteristics for morphologies, crystal structure, and element analysis were carried out by SEM, HR-TEM, and EDS respectively. And the defects of InN crystalline were analyzed by indexing of selective area diffraction pattern with attached HR-TEM. We have successfully obtained the defect-free 1-dimensional InN single crystalline nanowire at the atmosphere pressure.

• Journal of Korea Technology Innovation Society
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• v.7 no.1
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• pp.42-63
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• 2004

Recent trend of rapid growth in the basic research activities in East-Asian newly industrialized countries bring about the change in the world knowledge production structure. Particularly, Korea showed the changing patterns not only in the number of publication, but also in the aspect of structural change of basic research activities. The stylized facts of basic research activities in Korea can be summarized in three aspects; first, selective development patterns, second, reverse pattern of evolution, and finally, the rapid growth of basic research activities in major firms. This paper analyse the evolutionary patterns of basic research activities in empirical base and propose the policy implication for supporting basic research activity in newly industrializing countries.