• Restorative Dentistry and Endodontics
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• v.31 no.6
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• pp.445-451
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• 2006

The purposes of this study were to compare the effects of one or two applications of all-in-one adhesives on microtensile bond strengths (${\mu}$TBS) to unground enamel and to investigate the morphological changes in enamel surfaces treated with these adhesives using a scanning electron microscopy (SEM). Twenty-five noncarious, unrestored human mandibular molars were used. The unground enamel surfaces were cleansed with pumice. The following adhesives were applied to lingual, mid-coronal surfaces according to manufacture's directions; Clearfil SE bond in SE group, Adper Prompt L-Pop$^{TM}$1 coat in LP1 group, 2 coats in LP2 group, Xeno$^{\R}$III1 coat in XN1 group, and 2 coats in XN2 group. After application of the adhesives, a hybrid light-activated resin composite was built up on the unground enamel. Each tooth was sectioned to make a cross-sectional area of approximately 1.0 mm$^2$ for each stick. The microtensile bond strength was determined. Each specimen was observed under SEM to examine the morphological changes. Data were analyzed with one-way ANOVA. The results of this study were as follows; 1. The microtensile bond strength values were; SE (19.77 ${\pm}$ 2.44 MPa), LP1 (13.88 ${\pm}$ 3.67 MPa), LP2 (14.50 ${\pm}$ 2.52 MPa), XN1 (14.42 ${\pm}$ 2.51 MPa) and XN2 (15.28 ${\pm}$ 2.79 MPa). SE was significantly higher than the other groups in bond strength (p < 0.05). All groups except SE were not significantly different in bond strength (p < 0.05). 2. All groups were characterized as shallow and irregular etching patterns.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.856-861
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• 2002

Surface-modified powders were produced by hybridization system using core freeze-dried lactic acid bacteria (Lactobacillus acidophilus ATCC 43121) and enteric coating materials. Scanning electron microscopy showed that the surface of freeze-dried lactic acid bacteria changed to smooth round shape during surface reforming process, although no significant physical damages affecting the activity of the lactic acid bacteria were observed based on viability and salt-tolerance tests. Signigicant difference was not found in acid tolerance test probably due to the inherent acid tolerance of L. acidophilus ATCC 43121. Significantly improved heat tolerance was obtained by surface modification process. Among the tested coating materials, Sureteric showed a higher surface- reforming ability than Eudragit S100 and L100-55. Core : coating ratio agent of 9 : 1 (w/w) with rotor speed of 15,000 rpm for 3 min were determined to be optimum conditions for the process.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.2
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• pp.233-240
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• 2007

The purpose of this study was to evaluate the effect of different saccharides on the quality of apricot sulgidduk. Appearance color of honey-added group as compared to other samples in apricot sulgidduk were preferable and scanning electron microscopy exhibited smaller pores. pH and acidity of white-added group immediately after preparation were higher than those of other groups. Higher moisture contents of honey-added groups during storage were found but total bacterial counts immediately before storage were 1 log cycle lower than that of other samples. The highest 'L' values were found for white sugar added group but the highest 'a' and 'b' were for yellow sugar-added sample. In mechanical characteristics of apricot sulgidduk for 48 hrs during storage at $20^{\circ}C$, hardness, gumminess and brittleness were higher in oligosaccharide-added sample as compared to other samples, while cohesiveness and springiness were the highest in honey-added group. In sensory evaluation of the sulgidduk, honey-added group obtained the highest score in color, sweet taste, moisture, after swallowing and overall quality (p<0.05) These results suggest that apricot sulgidduk with honey can be used as commercially successful rice cakes.

• 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 Society of Food Science and Nutrition
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• v.40 no.9
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• pp.1285-1291
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• 2011

This study was conducted to evaluate the effect of lotus leaf and lotus root powder on the quality characteristics of sponge cake. Percentages of 4, 8 and 12% of two kinds of lotus powder were added to the batter based on flour content. Baking and cooling loss rate, volume and specific loaf volume, crumb color, texture, scanning electron microscopy (SEM) and sensory evaluation of the products were analyzed. The baking and cooling loss rate of the control was lower than cakes with added lotus leaf and lotus root powder. The volume of the control was the largest, and as the amount of lotus leaf and lotus root powder increased, volume and specific loaf volume became smaller. The lightness and yellowness values of the control were higher than those of the experimental cakes, and the loaves with 12% added lotus root powder showed the lowest value. Redness of the experimental cakes increased. In the textual property evaluation, hardness of the control and sponge cakes containing 4% lotus leaf, and lotus root powder appeared to have the lowest value. As the amount of lotus leaf and lotus root powder increased, hardness increased. Springiness showed the same tendency, but cohesiveness of the control revealed the lowest value. The structure of the cake crumb by SEM, revealed that the crumb cells and grains of the experimental cakes were opened and coarse, as the amount of lotus leaf and lotus root powders increased. In a sensory evaluation, sponge cakes containing lotus root powder were preferred rather than those with lotus leaf powder. As a result, good sponge cakes were prepared by adding 4% lotus leaf powder or 8% lotus root powder.

• Korean Journal of Plant Taxonomy
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• v.37 no.3
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• pp.239-254
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• 2007

A comparative micromorphological study was examined on the leaves of the genus Glechoma and related genera (Nepetinae, Lamiaceae) by scanning electron microscopy (SEM) in order to evaluate their significance in the taxonomy. The leaves of taxa Marmoritis, Nepeta sect. Glechomanthe, G. hederacea var. longituba (Korea) are revealed amphistomatic type, while the remnants of taxa had hypostomatic type. The size range of the guard cells is $12.50-28.75{\times}9.17-21.25{\mu}m$: the smallest one was found in M. pharicus ($12.50-15.83{\times}9.17-11.25{\mu}m$), while the largest one was measured to G. hederacea var. longituba (Korea: $28.75-28.88{\times}21.25-21.38{\mu}m$). The stomatal type of genera Agastache, Dracocephalum was mostly diacytic, however for the rest rarely together with anisocytic and anomocytic, except G. hederaca var. longituba (Korea), Meehania urticifolia by having combined with diacytic and anomocytic. The shapes of epidermal cells are differ from in abaxial and adaxial side, and dived with two types (e.g., platelet, stripe pattern). Five types (three glandular, two non-glandular hairs) of trichomes are distributed in leaves. Among trichomes, long and stalk capitates glandular trichome, subsessile glands are different from studied taxa so that leaf micromorphological characters are significance features in the taxonomy.

• Journal of the Microelectronics and Packaging Society
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• v.8 no.3
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• pp.49-53
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• 2001

Vortical etching experiments of ($SrBi_2Ta_2O_9$)/Si thin films have been performed by using the inductively coupled plasma reactive ion etching (ICP-ME) apparatus. The purposes of these experiments are to get the effective area of vertical surface. Because this technology is very important to get good qualities of ferroelectric gate structure, capacitor and the minimum parasitic effects related to the excellent performances of the FRAM (Ferroelectric Random Access Memory) device. The reacting gases were Ar and $Cl_2$gases, and various $Ar/C1_2$flow ratios were used. The etching experiments were carried out at various RF powers such as 700, 700, 500W and at various DC powers such as 200, 150, 100, 50W, respectively. The maximum etch rate of $SrBi_2Ta_2O_9$/Si thin films was 1050 A/min at the $Ar/C1_2$ gas ratio of 20/16, RF power of 700 W and DC power of 200 W. From the SEM (scanning electron microscopy) image of the SBT thin films, the wall angle was as good as about $82^{\circ}$.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.23 no.2
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• pp.108-113
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• 2013

Chalcopyrite material $CuInSe_2$ (CIS) is known to be a very prominent absorber layer for high efficiency thin film solar cells. Current interest in the photovoltaic industry is to identify and develop more suitable materials and processes for the fabrication of efficient and cost-effective solar cells. Various processes have been being tried for making a low cost CIS absorber layer, this study obtained the CIS nanoparticles using commercial powder of 6 mm pieces for low cost CIS absorber layer by high frequency ball milling and cryogenic milling. And the CIS absorber layer was prepared by paste coating using milled-CIS nanoparticles in glove box under inert atmosphere. The chalcopyrite $CuInSe_2$ thin films were successfully made after selenization at the substrate temperature of $550^{\circ}C$ in 30 min, CIS solar cell of Al/ZnO/CdS/CIS/Mo structure prepared under various deposition process such as evaporation, sputtering and chemical vapor deposition respectively. Finally, we achieved CIS nanoparticles solar cell of electric efficient 1.74 % of Voc 29 mV, Jsc 35 $mA/cm^2$ FF 17.2 %. The CIS nanoparticles-based absorber layers were characterized by using EDS, XRD and HRSEM.

• Journal of the Korean Chemical Society
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• v.50 no.1
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• pp.32-36
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• 2006

films of gold nanoparticles were formed on indium tin oxide (ITO) by an electrodeposition method from an aminosilicate stabilized gold colloid solution. The thin films were examined by cyclic voltammetry (CV), scanning electron microscopy (SEM), UV-visible, and energy dispersive X-ray spectroscopy (EDXS). The surface coverage of gold nanoparticles on the thin film was estimated to 1.2 nanomole/cm2. An anthraquinone-2, 6-disulfonic acid, disodium salt (AQDS) self-assembled layer was generated by immersing gold thin film into 1mM of AQDS in 0.1M HClO4 solution for over 20 hours. As a result, a new absorbance peak from the multi-layers (AQDS/thin film of gold /ITO) was obtained about at 690 nm. Also, the surface plasmon absorption of multi-layers was measured by UV-Visible spectrometer along with chronoamperometry by applying the various potentials from +0.5V to -0.5V. The maximum surface plasmon absorption band at 550 nm was decreased by applying negative potentials. The change of absorbance was correlated with the surface coverage of the AQDS indicating the pseudo-capacity surface state of the AQDS layer was coupled to the energy level of the plasmonband by applied negative potentials.

• Clinical and Experimental Reproductive Medicine
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• v.26 no.2
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• pp.193-201
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• 1999

In this study we determined fertilization processes and developmental ability of porcine oocytes following injection of round spermatid in the presence of artificial activation. Electrical stimulation at 3 h before spermatid injection significantly increased the incidence of normal fertilization as compared to those following injection without stimulation or with stimulation immediately after injection. The incidences of two pronuclear formation and apposition were not different in oocytes between following intracytoplasmic spermatid and spermatid nucleus injection. Indirect immunocytochemistry and laser scanning confocal microscopy study revealed that micro tubules were organized from the oocyte cortex following round spermatid injection, and this seemed to move both male and female pronuclei into the oocyte center. Paternal mitochondria which are introduced with spermatid have been observed up to 4-cell. Our study indicated that either round spermatid or it's nucleus can be used to produce viable bovine embryos by injection into unfertilized oocytes.