• Korean Journal of Materials Research
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• v.14 no.7
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• pp.482-488
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• 2004

$SiO_2$ nanowires were synthesized using the vapor evaporation method. Grown nanowires had a different shapes by kind of substrates. Diameters and lengths of the nanowires increased with increasing growth temperature and time. Mean diameters and lengths of $SiO_2$ nanowire were different by kind of substrates. These variations were attributed to nanowire densities on the substrates. The kind of substrates affected microstructure and PL properties of grown nanowires. In case of $Al_{2}O_3$ and quartz substrates, additional $O_2$ were supported during growth stages, and made a nucleation site. Therefore relative narrow nanowire was grown on $Al_{2}O_3$ and quartz substrates. Optical property were measured by photoluminescence spectroscopy. Relatively broad peak was obtained and mean peak positioned at 450 and 420nm. however in case of quartz substrates, mean peak positioned at 370nm. These peak shift was contributed to the size and substrate effects.

• Korean Journal of Medicinal Crop Science
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• v.20 no.4
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• pp.217-221
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• 2012

This research was conducted to investigate the influence of various organic substrates on growth and yield of ginseng seedling grown organically in the closed plastic house. The pH and EC of substrates used for organically ginseng cultivation ranged 5.93~6.78 and 0.03~0.15 dS/m respectively. The concentrations $NH_4$-N and $NO_3$-N respectively was 14.01~68.63 mg/L, 5.60~58.83 mg/L. The average quantum of the closed plastic house was range from 10 to 16% of natural light. In July and August, the maximum temperature of the closed plastic house did not exceed 30 and the average temperature was maintained within 25 lower than the field because air conditioning ran. The PPV-1 and PPV-2 bed soil substrates produced higher stem length, stem diameter, shoot fresh weight and leaf area than those of conventional culture. In PPV-2 bed soil substrates, root fresh weight and root diameter was the highest. The root fresh weight of PPV-2 bed soil substrates in closed plastic house was maximum 25% heavier than the conventional cultivation. The results of this experiment will be utilized for making new substrate application for organic ginseng culture in the plastic house.

• Korean Journal of Materials Research
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• v.16 no.4
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• pp.218-224
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• 2006

RF sputtering process was applied to produce thin hydroxyapatite(HAp) films on Ti-6Al-4V alloy substrates. The effects of different heat treatment conditions on the hardness between HAp thin films and Ti-6Al-4V alloy substrates were studied. Before deposition, the Ti-6Al-4V alloy substrates were heat treated for 1h at $850^{\circ}C\;under\;3.0{\times}10^{-3}torr$, and after deposition, the HAp thin films were heat treated for 1h at $400^{\circ}C,\;600^{\circ}C\;and\;800^{\circ}C$ under the atmosphere, and analyzed FESEM-EDX, FTIR, XRD, nano-indentor, micro-vickers hardness, respectively. Experimental results represented that the surface defects of thin films decreased by relaxation of internal stress and control of substrate structure followed by heat treatment of substrates before the deposition, and the HAp thin films on the heat-treated substrates had higher hardness than none heattreated substrates before the deposition, and the hardness properties of HAp thin films and Ti-6Al-4V alloy substrates appeared independent behavior, and the hardness of HAp thin films decreased by formation of $VTiO_3(OH),\;{\theta}-Al_{0.32}V_2O_5,\;Al_{0.33}V_2O_5$.

• Journal of Bio-Environment Control
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• v.10 no.2
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• pp.106-110
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• 2001

In an effort to evaluate the economic value and durability of the expanded rice hull as substrates, changes in the physical and chemical properties of material and plant growth in that substrate were studied. Using and electron microscope, the structure of used and new expanded rice hull substrate was examined. Considerable decomposition was found in the substrate which had been used one to three times. Compactness and lowered porosity in the used substrates were probably caused by decomposition. The results of cation analysis showed the possible destruction of cell wall of rice hulls. Abundant $Ca^{2+}$ in the substrates used for two to three times also indicated the possibility of decomposition. In tomato yield comparison, 15.2% more yield of tomato fruit in a new substrates indicated the negative effects of decomposition of one-time used substrates. Yield decreased in the substrates used for three times. if perlite substrates is used for three years before renewal and the cost of the perlite renewal is counted. 65.3% saving in the cost will be realized with the use of an expanded rice hull substrate. Another positive effect of the expanded rice hull substrate is the decrease of environmental contamination.n.

• Journal of Periodontal and Implant Science
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• v.47 no.2
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• pp.116-131
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• 2017

Purpose: The entry of bacteria or harmful substances through the epithelial seal of human gingival keratinocytes (HGKs) in the junctional epithelium (JE) is blocked by specialized intercellular junctions such as E-cadherin junctions (ECJs). However, the influence of roughened substrates, which may occur due to apical migration of the JE, root planing, or peri-implantitis, on the development of the ECJs of HGKs remains largely unknown. Methods: HGKs were cultured on substrates with varying levels of roughness, which were prepared by rubbing hydrophobic polystyrene dishes with silicon carbide papers. The activity of c-Jun N-terminal kinase (JNK) was inhibited with SP600125 or by transfection with JNK short hairpin RNA. The development of intercellular junctions was analyzed using scanning electron microscopy or confocal laser scanning microscopy after immunohistochemical staining of the cells for E-cadherin. The expression level of phospho-JNK was assessed by immunoblotting. Results: HGKs developed tight intercellular junctions devoid of wide intercellular gaps on smooth substrates and on rough substrates with low-nanometer dimensions (average roughness $[Ra]=121.3{\pm}13.4nm$), although the ECJs of HGKs on rough substrates with low-nanometer dimensions developed later than those of HGKs on smooth substrates. In contrast, HGKs developed short intercellular junctions with wide intercellular gaps on rough substrates with mid- or high-nanometer dimensions ($Ra=505.3{\pm}115.3nm$, $867.0{\pm}168.6nm$). Notably, the stability of the ECJs was low on the rough substrates, as demonstrated by the rapid destruction of the cell junction following calcium depletion. Inhibition of JNK activity promoted ECJ development in HGKs. JNK was closely associated with cortical actin in the regulation of ECJs in HGKs. Conclusions: These results indicate that on rough substrates with nanometer dimensions, the ECJs of HGKs develop slowly or defectively, and that this effect can be reversed by inhibiting JNK.

• Horticultural Science & Technology
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• v.29 no.2
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• pp.95-101
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• 2011

The influence of physicochemical properties of root substrates on the growth of mother plants and occurrence of daughter plants in 'Seolhyang' strawberry propagation were investigated through plastic bag cultivation. Six different formulations of root substrates were coir dust + perlite (5:5, A), coir dust + perlite (6:4, B), coir dust + perlite (7:3, C), coir dust + coconut chip (7:3, D), coir dust + coconut chip (6:4, E), and peatmoss + vermiculite (5:5, v/v; F). The total porosities (TP) and container capacities (CC) of all root substrates were higher than 85% and 55%, respectively, indicating that all substrates were in the acceptable range. But the TP and CC of F substrate were 91.5% and 60%, respectively, which were the highest among the root substrates tested. In the soil chemical properties analyzed before planting and after harvesting of 'Seolhyang' strawberry mother plants, the root substrates of A, B, C, and F had higher electrical conductivity and $NO_3$-N concentrations than those of D and F. The root substrates of A, B, C, and F had heavier runner fresh and dry weights, longer runner lengths, and more daughter plant occurrence than those of D and F. The treatment F had higher tissue N content than any other treatments at 120 days after the transplanting of 'Seolhyang' strawberry and statistical differences were not observed among remained 5 substrates. The treatment of F also had the higher tissue contents of other nutrients except N analyzed at 120 days after transplanting. These results indicated that soil chemical properties rather than physical properties severely influenced the growth of runners and occurrence of daughter plants.

• Journal of Microbiology and Biotechnology
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• v.18 no.9
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• pp.1522-1528
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• 2008

The morphogenetic behavior of a tropical marine Yarrowia lipolytica strain on hydrophobic substrates was studied. Media containing coconut oil or palm kernel oil (rich in lauric and myristic acids) prepared in distilled water or seawater at a neutral pH supported 95% of the cells to undergo a transition from the yeast form to the mycelium form. With potassium laurate, 51 % of the cells were in the mycelium form, whereas with myristate, 32% were in the mycelium form. However, combinations of these two fatty acids in proportions that are present in coconut oil or palm kernel oil enhanced the mycelium formation to 65%. The culture also produced extracellular lipases during the morphogenetic change. The yeast cells were found to attach to the large droplets of the hydrophobic substrates during the transition, while the mycelia were associated with the aqueous phase. The alkane-grown yeast partitioned more efficiently in the hydrophobic phases when compared with the coconut oil-grown mycelia. A fatty acid analysis of the mycelial form revealed the presence of lauric acid in addition to the long-chain saturated and unsaturated fatty acids observed in the yeast form. The mycelia underwent a rapid transition to the yeast form with n-dodecane, a medium-chain aliphatic hydrocarbon. Thus, the fungus displayed a differential behavior towards the two types of saturated hydrophobic substrates.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.11
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• pp.961-968
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• 2009

In this work, transparent conductive oxide(TCO) films such as $In_2O_3-SnO_2$(ITO) and $In_2O_3-ZnO$(IZO) were prepared on polyethylene naphthalene(PEN) and glass substrates by using rf-magnetron sputtering system. The TCO films deposited on PEN substrate show very poor conductivity as compared to that of the TCO films deposited on glass substrates. From the results of the residual gas analysis(RGA) test, this poor stability of plastic substrate is presumed to be caused by the deteriorated adhesion between the TCO films and the plastic substrate due to outgassing from the plastic substrate during deposition of TCO films. From our experiment, it is found that the vaporization of some defects in the plastic substrates deteriorate the adhesion of the TCO films to the plastic substrate, because the most plastic substrates containing the water vapor and/or other adsorbed particles such as organic solvents. Mixing of these gases vaporized in the sputtering process will also affect the electrical property of the deposited TCO films. Inorganic thin composite $(SiO_2)_{40}(ZnO)_{60}$ film as a gas barrier layer is coated on the PEN substrate to protecting the diffusion of vapors from the substrate, so that the TCO films with an improved quality can be obtained.

• Journal of the Korean Ceramic Society
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• v.43 no.1 s.284
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• pp.38-41
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• 2006

Surface of PC (Polycarbonate) and PES (Polyethersulphone) treated by plasma modification with rf power from 50 W to 200 W substrates in Ar (3 sccm), $O_2$ (12 sccm) atmosphere. From the results of modified substrates in XPS (X-ray Photoelectron Spectroscopy), the ratio of oxide containing bond increased with rf power. As the rf power was 200 W, the contact angle was the lowest value of 14.09 degree. And the datum from AFM (Atomic Force Microscopy), rms roughness value of PES and PC substrates increased with rf power. We could deposit $Ta_2O_5$ with good adhesion on plasma treated PES and PC substrates using by in-situ rf magnetron sputter.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2000.04a
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• pp.103-108
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• 2000

The texture of Al/Ti thin films deposited on low-dielectric polymer substrates has been investigated. Fifty-nm-thick Ti films and 500-nm-thick Al-1%Si-0.5%Cu (wt%) films were deposited sequentially onto low-k polymers and SiO$_2$ by using a DC magnetron sputtering system. The texture of Al thin film was determined using X-ray diffraction (XRD) theta-2theta ($\theta$-2$\theta$) and rocking curve and the microstructure of Al/Ti films on low-k polymer and SiO$_2$ substrates was characterized by Transmission electron microscopy (TEM). hall thin films deposited on SiO$_2$ had stronger texture than those deposited on low-k polymer. The texture of Al thin films strongly depended on that of Ti films. Cross-sectional TEM resealed that Brains of Ti films on SiO$_2$ substrates had grown perpendicular to the substrate, while the grains of Ti films on SiLK substrates were farmed randomly. The lower degree of 111 texture of Al thin films on low-k polymer was due to Ti underlayer.