• The Journal of Advanced Prosthodontics
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• v.6 no.2
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• pp.79-87
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• 2014

PURPOSE. The aim of this study was to determine the efficiency of Erbium, Chromium: Yttrium-Scandium-Gallium-Garnet laser in different output powers for removing permanent resin cement residues and therefore its influence on microshear bond strength compared to other cleaning methods. MATERIALS AND METHODS. 90 extracted human molars were sectioned in 1 mm thickness. Resin cement was applied to surface of sliced teeth. After the removal of initial cement, 6 test groups were prepared by various dentin surface treatment methods as follows: no treatment (Group 1), ethylene diamine tetra acetic acid application (Group 2), Endosolv R application (Group 3), 1.25 W Erbium, Chromium:Yttrium-Scandium-Gallium-Garnet laser irradiation (Group 4), 2 W Erbium, Chromium:Yttrium-Scandium-Gallium-Garnet laser irradiation (Group 5) and 3.5 W Erbium, Chromium:Yttrium-Scandium-Gallium-Garnet laser irradiation (Group 6). The topography and morphology of the treated dentin surfaces were investigated by scanning electron microscopy (n=2 for each group). Following the repetitive cementation, microshear bond strength between dentin and cement (n=26 in per group) were measured with universal testing machine and the data were analyzed by Kruskal Wallis H Test with Bonferroni correction (P<.05). Fracture patterns were investigated by light microscope. RESULTS. Mean microshear bond strength ${\pm}$ SD (MPa) for each group was $34.9{\pm}17.7$, $32.1{\pm}15.8$, $37.8{\pm}19.3$, $31.3{\pm}12.7$, $44.4{\pm}13.6$, $40.2{\pm}13.2$ respectively. Group 5 showed significantly difference from Group 1, Group 2 and Group 4. Also, Group 6 was found statistically different from Group 4. CONCLUSION. 2 W and 3.5 W Erbium, Chromium: Yttrium-Scandium-Gallium-Garnet laser application were found efficient in removing resin residues.

• Journal of the Korean Geotechnical Society
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• v.28 no.10
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• pp.69-77
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• 2012

Clogging of drainage pipes by scale is an important problem in civil engineering works. Although scale deposits can be removed by acid treatment or water jetting, these treatments are costly and have many disadvantages. In this study, scale samples from tunnel drainage pipes were analyzed using SEM-EDS and XRD. The main ingredient in scale was $CaCO_3$ of the calcite crystal form. Drainage experiments and recirculation type experiments were conducted to control and remove scale deposits, which were determined through visual and weight measuring analysis. As a result, Quantum Stick has the effect of limiting formation of scale.

• Journal of the Mineralogical Society of Korea
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• v.18 no.2
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• pp.83-92
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• 2005

Dissolution rate of minerals may differ from climates configuration, but weathering rate of feldspars is generally proved to be relatively higher The result of geochemical reaction modeling indicates the acid water of pH 4.5 excluding any other variables, was 2.3 times higher than that in ordinary rain of pH 5.7. This result proved that pH is very important factor in preservation of granite cultural properties. To prevent the weathering of stone cultural properties, weathering characteristics of stones should be studied first and constitution of dry environments, using water repellent or oil coating, isolating water which cause chemical weathering reaction like hydration and oxidization should be considered. Considering the long-term reactions between granite and rain, selection of materials, which can bring neutralization and non-oxidization conditions, are very important in using cleaning agents and biological controls.

• Economic and Environmental Geology
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• v.30 no.3
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• pp.223-230
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• 1997

The skeletal chemistry of calcareous microfossils may contribute to the classification of various biological processes and be used as an environmental indicator for future pollution. In order to examine the degree of heavy metal pollutions in marine environments, samples of sediment and benthonic foraminifera were taken from 5 study areas from 3 different stations in coastal offshore regions of Korea. After sieving, cleaning and acid digestion, sample were analyzed for heavy metals by ICP-MS, ICP-AES and AAS. Concentrations of Cd, Cu, Pb and Zn in most of marine sediments from 5 study areas are not higher than those in sediments from unpolluted marine environment in the U.K.. However, pollution indices are up to 0.96~0.99 in the Gwangyang and Yulchon areas which are classified as the special control distric along the coast for pollution. The pollution indices decrease in order of Yulchon > Gwangyang > Mokpo > Gamak = Yoja > Yonggwang areas. Concentrations of Mg, Pb, Sr and Zn in Ammonia beccarii Pseudorotalia gaimardii, Quinqueloculina lamarckiana are reduced after pre-treatment of samples. From the result of bioconcentration index, Mg is easily accumulated in microfossils and Quinqueloculina lamarckiana may be used as the best indicator for future pollution.

• Journal of Fashion Business
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• v.16 no.1
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• pp.16-25
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• 2012

As the test results for surface color, dyeing durability, antibiosis of cotton fabrics and silk fabrics dyed with Agastache rugosa extract, the following conclusions were obtained. The surface color of all the dyed fabrics was confirmed mostly as a GY system. As the result of chrominance(${\Delta}E_{ab}$) measurement, in the case of cotton fabrics the dyed fabrics treated with $Al_2(SO_4)_3$ mordant showed the highest value and in the case of silk fabrics the non-mordant dyed fabrics showed the highest value. The dyeing durability of test fabrics dyed with Agastache rugosa extract are as follows. As the test results of colorfastness to laundry for cotton dyed fabrics, the discoloration degree showed 1st-2nd grade and the contamination degree showed 4th-5th grade. As the test result of colorfastness to dry cleaning for silk dyed fabrics, the contamination degree showed from 1st to 3rd-4th grade. As the test results of colorfastness to acid artificial perspiration, the discoloration degree showed from 1st to 3rd-4th grade and the contamination degree showed from 3rd to 4th-5th grade. As the test results of colorfastness to alkaline artificial perspiration, the discoloration degree showed from 1st to 4th grade and the contamination degree showed from 3rd to 4th-5th grade. The colorfastness to sunlight showed from 1st to 2nd grade. The colorfastness to rubbing showed from 3rd to 4th-5th grade in dry process and from 2nd-3rd to 4th-5th grade in wet process. As the test results of antibiosis, the decrease rate of germs to virus Klebsiella pneumoniae and Staphylococcus aureus showed at least more than 99% after the wash of 10 times. As the test results of antifungal activity to mycete Trichophyton mentagrophytes and Aspergillus niger, the both cotton and silk dyed fabrics didn't gain the significant antifungal effect.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.22 no.2
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• pp.41-51
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• 1996

Phaseolus aureus (mung bean), Leguminosae, has been used as an antidote from the ancient time. Especially, it has been widely used for cleaning face and skin in oriental countries. Although several constituents such as fatty acids, phytoallexin and phaseol derivatives were reported in P. aureus and related species including seedlings, there has been a few report to describe its biological activity. Therefore, in this investigation, the ethanol extract from P. aureus was obtained and its biological activities including the antioxidative and anti-inflammatory activities were studied. The 70% ethanol extract from P. aureus showed dose-dependent antioxidative activity (52.3% inhibition at 4 mg/ml) against lipid peroxidation assay, while the extract did not show the inhibitory activity of superoxide radical formation. The extract also showed the topical anti-inflammatory activity against croton-oil and arachidonic acid induced mouse ear edema test (18-19% inhibition at 7.5 mg/ear) as well as mild inhibitory activity against picryl chloride induced delayed hypersensitivity in mouse. For investigating active principles, vitexin and isovitexin (apigenin C-glycoside) as flavonoids, and adenosine were isolated from the extract using silica gel chromatography. The actual contents of vitexin and isovitexin were found to be 3.7 and 2.4 mg/g extract, respectively. Vitexin and isovitexin showed the antioxidative activity. They showed the topical anti-inflammatory activity, although the activities were not potent compared to the reference compounds. These results suggested that vitexin and isovitexin may be, at least in part, the compounds contributing the antioxidative activity in vitro and the topical anti-inflammatory activity of P. aureus in vivo. All results of present study might be one of the scientific rationale in using mung bean for skin care from the ancient time.

• The Research Journal of the Costume Culture
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• v.17 no.4
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• pp.575-582
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• 2009

The coffee has been used as drink in the world and it has been using not only food but also dyeing. It can be used for four seasons in our normal living and it can be taken friendly everywhere. The coffee consists of about 8${\sim}$10% phenol(chlorogenic acid) that related to antioxidant and antimicrobial activity. However, its exact components and the dyeing property effects has not been well known yet. Therefore, the purpose of this study was to investigate the dyeing property and ultraviolet-cut ability of silk and nylon fabrics that was dyed variously with coffee extracts. Coffee extracts were done by boiling coffee with distilled water at $100^{\circ}C$ for 2 hours. As mordanting agent, we used $AlK(SO_4)_2$ $12H_2O$, $CuSO_4$ $5H_2O$, $FeCl_2$ $4H_2O$. As the result of the dyeing properties and ultraviolet-cut ability of fabrics dyed with coffee bean extracts, we can find that the optimum dyeing temperature and dyeing time of the silk and nylon fabrics dyed with coffee bean extracts was $90^{\circ}C$, 60 min. and the colorfastness of washing and dry-cleaning was improved by using mordanting agent(4${\sim}$5 grade). Ultraviolet-cut ability was showed more 90% in dyed nylon fabrics.

• Journal of Korean Society of Water and Wastewater
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• v.31 no.4
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• pp.311-319
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• 2017

Scale formation is inevitable problem when seawater is treated by vacuum membrane distillation. The reason is the high concentration of calcium ion($Ca^{2+}$), sulfate ion(${SO_4}^{2-}$) and bicarbonate ion(${HCO_3}^-$). These ions form calcium sulfate($CaSO_4$) and calcium carbonate($CaCO_3$) on the membrane. The scale formed on membrane has to be removed, because the flux can be severely reduced and membrane wetting can be incurred. This study was carried out to investigate scale formation and effectiveness of acid cleaning in vacuum membrane distillation for SWRO brine treatment. It was found that permeate flux gradually declined until volume concentration factor(VCF) reached around 1.55 and membrane wetting started over VCF over 1.6 in the formation of precipitates containing $CaSO_4$ during VMD operation. In contrast, when calcium carbonate formed on membrane, permeate flux was gradually reduced until VCF 3.0. The precipitates containing both $CaSO_4$ and $CaCO_3$ were formed on the membrane surface and in the membrane pore.

• Journal of Periodontal and Implant Science
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• v.30 no.4
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• pp.821-836
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• 2000

The Peri-implantitis causes inflammation of periodontal tissue and bone loss. It contaminates surface of implants. Therefore, guided bone regeneration has been used for the treatment of this disease. For the reosseointegration of the exposed surface, various mechanical and chemical methods have been used for cleaning and detoxication of implant surface. Among these methods, air-powder abrasive and oversaturated citrate are known to be most effective. However, these treatments may deform implant surface. In this research, changes of surface roughness they were examined. 10 experimental machined titanium cylinder models were fabricated to be used for control groups. Each of them was air powder abraded for 1 minute and they were named group 1. And then, group 1 were burnished with cotton pellets soaked with citrate for 30 seconds(Group 2), 1 minute(Group 3), 3 minutes(Group 4), and 5 minutes(Group 5) burnishing were applied for grouping respectively. Each group were examined with SPM, and their surface roughness were measured and analyzed. 1. Surface roughness of titanium decreased when it was air-powder abraded for 1 minute. It was statistically significant. 2. When Air-powder abraded titanium were treated with citrate for 3 minutes, Their surface roughness was the lowest. Titanium treated for 1 minute was the second lowest and 30 seconds was the third and titanium burnished for 5 minutes was the highest. 3. Surface roughness of titanium which was treated with citrate was decreased till 3 minutes, which was statistically significant. There was no statistical significance from 30 seconds to 1 minute and from 1 minute to 3 minutes, and there was statistical significance from 30 seconds to 3 minutes. 4. Oxide layer was formed when titanium is exposed to air, and it was removed when air-powder abraded. It was made when treated with citrate. It is thought that citrate treatment is necessary after the air-powder abrasion, and 1 minute is clinically and qualitatively adequate for burnishing time of citrate.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.4
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• pp.246-251
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• 2003

The blood-brain barrier (BBB) is composed of the brain capillaries, which are lined by endothelial cells displaying extremely tight intercellular junctions. Several attempts at creating an in vitro model of the BBB have been met with moderate success as brain capillary endothelial cells lose their barrier properties when isolated in cell culture. This may be due to a lack of recreation of the in vivo endothelial cellular environment in these models, including nearly constant contact with astrocyte foot processes. This work is motivated by the hypothesis that growing endothelial cells on one side of an ultra-thin, highly porous membrane and differentiating astrocyte or astrogliomal cells on the opposite side will lead to a higher degree of interaction between the two cell types and therefore to an improved model. Here we describe our initial efforts towards testing this hypothesis including a procedure for membrane fabrication and methods for culturing endothelial cells on these membranes. We have fabricated a 1 $\mu\textrm{m}$ thick, 2.0 $\mu\textrm{m}$ pore size, and 55% porous membrane with a very narrow pore size distribution from low-stress silicon nitride (SiN) utilizing techniques from the microelectronics industry. We have developed a base, acid, autoclave routine that prepares the membranes for cell culture both by cleaning residual fabrication chemicals from the surface and by increasing the hydrophilicity of the membranes (confirmed by contact angle measurements). Gelatin, fibronectin, and a 50/50 mixture of the two proteins were evaluated as potential basement membrane protein treatments prior to membrane cell seeding. All three treatments support adequate attachment and growth on the membranes compared to the control.