• Restorative Dentistry and Endodontics
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• v.14 no.2
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• pp.38-48
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• 1989

The purpose of this study was to investigate the proper consistency of root canal sealer needed in obtaining an efficient canal obturation in injection-thermoplasticized low-temperature ($70^{\circ}C$) gutta-percha method. The sealer was made by incorporating zinc oxide powder into $0.5m{\ell}$ of eugenol and then the $0.5m{\ell}$ of mixture slurry was placed between two flat glass plates. The consistency was determined by measuring the degree of spread of the slurry at loading the 120gm of weight from the top plate. The sealer was prepared according to P/L ratio corresponding to the acquired consistency of 65.45mm, 46.80mm, 28.95mm and 22.60mm. The distal roots were obtained by cutting off from 125 extracted human lower molars and the root canals were prepared by using step-back method. The prepared canals were coated with the sealers on their walls and obturated by using the injection-thermoplasticized low-temperature ($70^{\circ}C$) gutta-percha method. All specimens were immersed in 2% methylene blue dye solution for 48 hours at $37^{\circ}C$. Calipers was used to measured the dye penetration into the root canals from apical constrictions. The results were as follows : The canals obturated without sealer showed significantly more leakage than the canals obturated with sealer. Within the consistency from 65.45mm to 22.60mm, the sealer of 65.45mm appeared significantly better than that of 28.95mm and 22.60mm in the canals obturated by injection-thermoplasticized gutta-percha method, and better than that of 46.80mm without statistical significance.

• Journal of the Korean Ceramic Society
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• v.53 no.3
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• pp.343-348
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• 2016

Manganese and $TiO_2$ grown on Activated Carbon Fiber (ACF) was synthesized by hydrothermal method. The prepared composites were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy dispersive X-ray (EDX). The catalytic behavior was investigated through the decomposition of methylene blue (MB) and methyl orange (MO) as standard dyes under visible light. The degradation performance of the degraded standard dye solutions was determined by UV-Vis spectrophotometry. This enhanced photocatalytic activity arises from the positive synergetic effect among the Mn, $TiO_2$ and ACF in this heterogeneous photocatalyst. The process contributes to the release of abundant photocatalytic sites of Mn and $TiO_2$ and improves the photocatalytic efficiency. The excellent adsorption and photocatalytic effect with the explanation of the synergetic mechanism are very useful not only for fundamental research but also for potential practical applications.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1657-1661
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• 2011

In this study, CdSe-$TiO_2$ photocatalyst were synthesized by a facile solvothermal method and characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis and UV-vis diffuse reflectance spectrophotometer. The photocatalytic activity was investigated by degrading methylene blue (MB) in aqueous solution under irradiation of UV light as well as visible light. The absorbance of degraded MB solution was determined by UV-vis spectrophotometer. The results revealed that the CdSe-$TiO_2$ photocatalyst exhibited much higher photocatalytic activity than $TiO_2$ both under irradiation of UV light as well as visible light.

• Textile Coloration and Finishing
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• v.21 no.5
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• pp.1-9
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• 2009

The feasibility of earthworm protease as a new cosmetic material for human hair care was investigated. The effectiveness of the earthworm protease treatment was assessed by thickness change of hairs, optical microscope examination, aminoacid analysis, surface morphology, angular resolution analysis through methylene blue staining method and tensile strength change. The protease treated hair became thinner and the soil on the surface removed in experimental groups unlike control group. Tensile strength decreased in experimental group in which the enzymes may decompose polypeptide bonds.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.90-90
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• 2010

We investigated the modification of optical response properties of titanium dioxide (TiO2) coatings on the ceramic water-purification filters by using ultraviolet-visible absorption spectroscopy and X-ray diffraction. The TiO2 coatings were prepared on ceramic substrate by e-beam evaporation method. These amorphous TiO2 were turned into anatase phase by heat treatment at $700^{\circ}C$ for 2 hours. The doping of N atoms into the TiO2 coatings was done by using 70KeV of N＋ ion implantation with the dose of $1.0{\times}1017$ ions/cm2, followed by post-irradiation heat treatment at $550^{\circ}C$ for 2 hours. Methylene blue test of TiO2 coatings to solar irradiation showed that the post-evaporation heated TiO2 was photocatalytic and N-doped TiO2 reacted to the visible part of solar irradiation.

• Journal of Chest Surgery
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• v.21 no.1
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• pp.17-25
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• 1988

This study was undertaken to evaluate the efficacies for myocardial protective effect of retrograde right atrial perfusion [RRAP] of cardioplegia compared with antegrade aortic root perfusion [AARP]. Myocardial distribution of perfusate [using methylene blue] with RRAP was less poor to AARP. Myocardial protective effect was estimated with myocardial temperature and electron microscopy. Cooling protection of right ventricle with RRAP was similar to AARP. On the other hand, cooling protection of left ventricle with RRAP was slight poor to AARP. The electron microscopic ischemic change of right and left ventricle with RRAP was similar to AARP. RRAP was thought to be a good alternative method to perfuse cardioplegia and protect both ventricle.

• Journal of Life Science
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• v.18 no.1
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• pp.91-95
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• 2008

In human, sympathetic nerve blocks with local anesthetics are widely used to treat a variety of diseases in the innervating regions. However, its procedure in dogs is difficult to approach and process repeatedly because of anatomically location. Therefore, this study was designed to develop a new technique of sympathetic nerve block in beagle dogs. Fifteen healthy beagle dogs, which did not show any neurologic abnormalities and disease, were used for the study. Radiograghs were taken after injected radiopaque material mixed with 2% lidocaine at the cranial cervical ganglion and injected methylene blue using the same percutaneous technique to verify the reliability of this newly developed technique. The successful block rate of the cranial cervical ganglion block was present in 80% of all dogs and the stained cranial cervical ganglions were shown in all dogs. The results show that this new technique of the cranial cervical ganglion block is a reliable and simple method that can be used for clinical studies in dogs.

• Restorative Dentistry and Endodontics
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• v.16 no.1
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• pp.181-189
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• 1991

The purpose of this study was to evaluate the effect of apical seal produced by ultrasonic instrumentation. 120 extracted, permanent single rooted teeth were randomly divided into 6 groups of 20 teeth and root canals were enlarged & obturated according to Table I. After canal obturation, the obturated teeth were immersed in 2.5 % Methylene blue for 72 hrs. at $37^{\circ}C$ incubator and longitudinally sectioned. The apical sealing ability was evaluated by measuring the degree of dye penetration into the canal. The results were as follows: 1. All groups showed varying depth of dye penetration. 2. There were no significant differences between Group I and N, Group II and V, Group III and VI. (P>0.05) 3. Regardless of obturation method, there were no significant differences between hand instrumented group and ultrasonic instrumented group.(P>0.05).

• Journal of the Korean Ceramic Society
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• v.48 no.3
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• pp.211-216
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• 2011

Nickel oxide-doped ACF and $TiO_2$ composites (NiO/ACF/$TiO_2$) were prepared by a sol-gel method. The composite obtained was characterized by BET surface area measurements, X-ray diffraction, transmission electron microscopy and energy dispersive X-ray analysis. A methylene blue (MB) solution under visible light irradiation was used to determine their photocatalytic activity. Excellent photocatalytic degradation of the MB solution was observed using the $TiO_2$, Ti-ACF and NiO/ACF/$TiO_2$ composite under visible light.

• YAKHAK HOEJI
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• v.27 no.2
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• pp.125-131
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• 1983

Whether ($AB_{w}$) may be neglected against ($A_{w}^{+}$) in the calculation of the extraction coefficient of ion-pairs was criticized by both experiments and theoretical consideration, where ($AB_{w}$) and ($A_{w}^{+}$) mean the molar concentration of ion-pair AB and cation $A^{+}$ in the aqueous phase. Ion-pair complexes were partitioned between phosphate buffer (pH 7.4) and n-octanol. Tetrabutylammonium, isopropamide and methylene blue were selected as cations and benzoic acid, p-toluenesulfonic acid, salicylic acid and taurodeoxycholic acid were selected as counter ions (anions). As a result, conventional methods which assume no existence of ($AB_{w}$) were proven to lack generality. The equation proposed in my earlier report was confirmed to be valid as a general method.