• 한국해양공학회지
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• 제25권1호
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• pp.32-38
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• 2011

Galvanized steel has gone through a chemical process to keep it from corroding. The steel gets coated in layers of zinc because rust will not attack this protective metal. For countless outdoor, marine, or industrial applications, galvanized steel is an essential fabrication component. The reduction of the corrosion rate of zinc is an important topic. In the past, a very popular way to reduce the corrosion rate of zinc was to use chemical conversion layers based on $Cr^{+6}$. However, a significant problem that has arisen is that the use of chromium salts is now restricted because of environmental protection legislation. Therefore, it is very important to develop new zinc surface treatments that are environmentally friendly to improve the corrosion resistance of zinc and adhesion with a final organic protective layer. In this study, a Urethane solution (only Urethane 20 wt.%; S-700) and an organic/inorganic solution with Si (Si polysilicate 10 wt.% + Urethane 10 wt.%; LRO-317) are used. Based on the salt spray test of 72 h, S-700 and LRO-317 had a superior effect for the corrosion resistance on EGI and HDGI, respectively.

• Corrosion Science and Technology
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• 제9권1호
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• pp.29-33
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• 2010

Laser machining technique, which is used focusing pulse YAG laser beam irradiation was applied to form area ratio controlled model cut-edge on pre painted Zn coated steels. A corrosion behavior of formed model cut-edge was investigated by rest potential measurement in 1 mol $m^{-3}$ NaCl with and without 0.5 kmol $m^{-3}$ $H_3BO_4$/0.05kmol$m^{-3}$ $Na_2B_4O_7$. The rest potential showed almost constant value with fluctuations. The amplitude of fluctuations increased with exposed area of steel surface. White corrosion products of zinc oxide and simonkollite was formed after the experiments at the formed model cut-edge.

• Restorative Dentistry and Endodontics
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• 제33권4호
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• pp.369-376
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• 2008

이 연구의 목적은 3 종의 포틀랜드 시멘트 (포틀랜드 시멘트, 백색 포틀랜드 시멘트, 초속경 시멘트)와 white MTA의 성분 및 세포독성을 비교하는 것이다. 성분비교를 위해서 X선 회절기 (XRD), X선 형광분석기 (XRF), 유도결합플라즈마 원자방출분광 분석기 (ICP-AES)를 사용하였으며, 세포독성비교를 위해서는 우무확산법 (agar diffusion test)을 사용하였다. 분석 결과, white MTA와 백색 포틀랜드 시멘트는 포틀랜드 시멘트나 초속경 시멘트에 비해 적은 양의 마그네슘 (mg), 철 (Fe), 아연 (Zn), 그리고 망간 (Mn)을 함유하고 있었다. 또한 초속경 시멘트는 다른 시멘트 및 white MTA에 비해 많은 산화 알루미늄 ($Al_2O_3$)을 함유하고 있었다. MTA와 포틀랜드 시멘트의 주된 성분은 tricalcicium silicate ($3CaO{\cdot}SiO_2$), dicalcium Silicate ($2CaO{\cdot}SiO_2$), tricalcium aluminate ($3CaO{\cdot}Al_2O_3$), 그리고 tetracalcium aluminoferrite (4CaO{\cdot}Al_2O_3{\cdot}Fe_2O_3)등이었다 세포독성 실험결과를 Kruskal-Wallis Exact test와 Bonferroni 사후 검정법을 사용하여 분석 한 결과 white MTA와 3 종의 포틀랜드 시멘트 군 사이에서 통계적으로 유의성 있는 차이를 보이지 않았다 (p > 0.05). White MTA와 3종의 포틀랜드 시멘트의 주성분은 유사하였으나 알루미늄 (Al), 마그네슘 (mg), 철 (Fe), 아연 (Zn), 그리고 망간 (Mn) 등의 함량에서는 차이를 보였으며 이러한 차이들은 물리적 성질에 영향을 미칠 것으로 보인다.

• 한국수산과학회지
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• 제45권4호
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• pp.307-316
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• 2012

This study evaluated the possible use of white muscle from cooked skipjack tuna as a constituent of diet foods. White muscles from the belly and dorsal area of cooked skipjack tuna were identified as anterior, median, and posterior. The skipjack tuna white muscle contained more moisture and ash (except for part I in both the belly and dorsal muscles) than chicken muscle, while it had less crude protein and crude lipid (except for part II in belly muscle). The yield was the highest in part I of both the dorsal and belly parts among the various parts of white muscles. The skipjack tuna white muscle contained 14-18% fewer calories than chicken breast muscle. Part I from both the belly and dorsal muscles had higher total amino acid contents than the other parts, but lower contents than chicken breast muscle. White muscle of skipjack tuna was rich in minerals, such as phosphorus, iron, and zinc. The total free amino acid content of part I in the belly and dorsal muscles was 1,152.1 and 1,215.7 mg/100 g, respectively, and was 1.7-1.8 times higher than in chicken breast muscle. The major amino acids in the white muscles from skipjack tuna were taurine, histidine, anserine, and carnosine. Based on these results, if it is possible to mask the fish odor, all parts of the white muscle from skipjack tuna could be used as constituents of diet foods.

• Journal of Nutrition and Health
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• 제57권2호
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• pp.171-184
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• 2024

Purpose: Although activating thermogenic adipocytes is a promising strategy to reduce the risk of obesity and related metabolic disorders, emerging evidence suggests that it is difficult to induce adipocyte thermogenesis in obesity. Therefore, this study aimed to investigate the regulation of adipocyte thermogenesis in diet-induced obesity. Methods: Adipose progenitor cells were isolated from the white and brown adipose tissues of control diet (CD) or high-fat diet (HFD) fed mice, and fully differentiated white and brown adipocytes were treated with β-agonists or 18-carbon fatty acids for β-adrenergic activation or peroxisome proliferator-activated receptor (PPAR) activation. Results: Compared to the CD-fed mice, the expression of uncoupling protein 1 (Ucp1) was lower in the white adipose tissue of the HFD-fed mice; however, this was not observed in the brown adipose tissue. The expression of peroxisome proliferator-activated receptor gamma (Pparg) was lower in the brown adipose progenitor cells isolated from HFD-fed mice than in those isolated from the CD-fed mice. Norepinephrine (NE) treatment exerted lesser effect on peroxisome proliferator-activated receptor-γ coactivator (Pgc1a) upregulation in white adipocytes derived from HFD-fed mice than those derived from CD-fed mice. Regardless which 18-carbon fatty acids were treated, the expression levels of thermogenic genes including Ucp1, Pgc1a, and positive regulatory domain zinc finger region protein 16 (Prdm16) were higher in the white adipocytes derived from HFD-fed mice. Oleic acid (OLA) and γ-linolenic acid (GLA) upregulated Pgc1a expression in white adipocytes derived from HFD-fed mice. Brown adipocytes derived from HFD-fed mice had higher expression levels of Pgc1a and Prdm16 compared to their counterparts. Conclusion: These results indicate that diet-induced obesity may downregulate brown adipogenesis and NE-induced thermogenesis in white adipocytes. Also, HFD feeding may induce thermogenic gene expression in white and brown primary adipocytes, and OLA and GLA could augment the expression levels.

• 한국응용과학기술학회지
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• 제17권1호
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• pp.63-66
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• 2000

Organic Electroluminescent devices(OELD) consisted of multilayer structures have been studied for the application the application to flat-panel display. Metal-chelate complexes, zinc bis(2-(2-hydroxyphenyl)benzoxazolate) ($Zn(BOX)_{2}$) and zinc bis(2-(2-hydroxyphenyl)benzothiazolate) ($Zn(BOX)_{2}$), have been intensively investigated as an white-light emitting layer and recognized to have good electroluminescent(EL) properties. In this study, ($Zn(BOX)_{2}$) and ($Zn(BTZ)_{2}$) were synthesized and characterized by FT-IR, $^{1}H-NMR$, UV-VIS and PL. Their EL properties were also studied and their ionization potential(IP) and electron affinity(EA) were also measured by cyclic voltammetry(CV).

• 한국표면공학회지
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• 제51권4호
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• pp.237-242
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• 2018

We report on the fabrication and photoelectrochemical (PEC) properties of a ZnO nanorod array structure as an efficient photoelectrode for hydrogen production from sunlight-driven water splitting. Vertically aligned ZnO nanorods were grown on an indium-tin-oxide-coated glass substrate via seed-mediated hydrothermal synthesis method with the use of a ZnO nanoparticle seed layer, which was formed by thermally oxidizing a sputtered Zn metal thin film. The structural and morphological properties of the synthesized ZnO nanorods were examined using X-ray diffraction and scanning electron microscopy, as well as Raman scattering. The PEC properties of the fabricated ZnO nanorod photoelectrode were evaluated by photocurrent conversion efficiency measurements under white light illumination. From the observed PEC current density versus voltage (J-V) behavior, the vertically aligned ZnO nanorod photoelectrode was found to exhibit a negligible dark current and high photocurrent density, e.g., $0.65mA/cm^2$ at 0.8 V vs Ag/AgCl in a 1 mM $Na_2SO_4$ electrolyte. In particular, a significant PEC performance was observed even at an applied bias of 0 V vs Ag/AgCl, which made the device self-powered.

• 보존과학회지
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• 제36권1호
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• pp.47-59
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• 2020

Scientific analysis was conducted to identify the paint pigments used in the Buseoksa Josadang murals. optical microscopy(OM), X-ray fluorescence(XRF), XRF mapping, scanning electron microscopy-energy dispersive X-ray spectroscopy(SEM-EDS), and Raman spectroscopy were performed to examine the pigments. The results confirmed that the Josadang murals consist of two paint layers wherein the pigments were distinct for most colors. It was estimated that celadonite, white clay, red ochre, cinnabar and minium, synthetic green pigment containing tin and zinc paratacamite, or botallackite were used in the upper layer. In addition, bone white, celadonite, red ochre, azurite, cinnabar or vermilion, and gold were identified in the lower layer. In addition, as Zn and Sn were detected in the green pigments extracted from the top layer of the paint, it is believed that Josadang murals were repainted over the original paint layer at some point after the 17th century. In addition, white pigments containing calcium phosphate were found in all the colors in the bottom layer, which is the original paint layer. These results are significant because this is the first time that white pigments are found in Korean traditional paintings. Additionally, the information revealed about the pigments in this study will serve as areference for the pigments used in the Goryeo period.

• 한국수산과학회지
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• 제51권5호
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• pp.491-498
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• 2018

The objective of this study was to investigate the composition of canned oyster Crassotrea gigas in white sauce (CO-WS). The proximate composition of CO-WS was 74.1% water, 10.4% crude protein, 4.9% crude lipid, and 3.1% ash. The energy converted based on these percentages was 112.2 kcal/100 g, while the salinity was 1.1 g/100 g. In a taste-intensity test using an electronic tongue, the CO-WS showed higher umami taste intensity than the control (canned oyster in commercial white sauce), whereas the intensities of the other tastes (salty, sour, bitter, and sweet) were lower. Because the odor intensity was low, CO-WS was considered to have a relatively weak odor and showed no difference in hardness compared to the control. Sensory evaluation of CO-WS by a panel yielded higher scores for appearance, taste, and texture, and a lower score for flavor compared to the control. The total amino acid content of CO-WS was 8.91 g/100 g, and its major amino acids were aspartic acid, glutamic acid, and leucine. With respect to mineral content, CO-WS had higher calcium and lower zinc contents than the control. These results suggest that CO-WS has excellent nutritional value.

• Journal of Microbiology and Biotechnology
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• 제27권3호
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• pp.480-491
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• 2017

Fluorescent pseudomonads have been isolated from halophytes, mesophytes, and xerophytes of Pakistan. Among these, eight isolates, GS-1, GS-3, GS-4, GS-6, GS-7, FS-2 (cactus), ARS-38 (cotton), and RP-4 (para grass), showed antifungal activity and were selected for detailed study. Based on biochemical tests and 16S rRNA gene sequences, these were identified as strains of P. chlororaphis subsp. chlororaphis and aurantiaca. Secondary metabolites of these strains were analyzed by LC-MS. Phenazine-1-carboxylic acid (PCA), 2-hydroxy-phenazine, Cyclic Lipopeptide (white line-inducing principle (WLIP)), and lahorenoic acid A were detected in variable amounts in these strains. P. aurantiaca PB-St2 was used as a reference as it is known for the production of these compounds. The phzO and PCA genes were amplified to assure that production of these compounds is not an artifact. Indole acetic acid production was confirmed and quantified by HPLC. HCN and siderophore production by all strains was observed by plate assays. These strains did not solubilize phosphate, but five strains were positive for zinc solubilization. Wheat seedlings were inoculated with these strains to observe their effect on plant growth. P. aurantiaca strains PB-St2 and GS-6 and P. chlororaphis RP-4 significantly increased both root and shoot dry weights, as compared with uninoculated plants. However, P. aurantiaca strains FS-2 and ARS-38 significantly increased root and shoot dry weights, respectively. All strains except PB-St2 and ARS-38 significantly increased the root length. This is the first report of the isolation of P. aurantiaca from cotton and cactus, P. chlororaphis from para grass, WLIP and lahorenoic acid A production by P. chlororaphis, and zinc solubilization by P. chlororaphis and P. aurantiaca.