• Proceedings of the KWS Conference
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• 2009.11a
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• pp.205-209
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• 2009

Wetting properties between silver-copper-titanium braze alloys with different titanium contents up to 2.8 mass% and hexagonal boron nitride ceramics were investigated using sessile drop method at 1123K in Argon. The final contact angle is less than $30^{\circ}$ when the Ti content was over 0.41 mass%. Meanwhile, the contact angle curves show different behavior. In case of using braze alloy containing 2.8 mass% of titanium, the initial contact angle is acute angle just after the melting of braze. In case of brazes containing titanium less than 2.26 mass%, the contact angle is larger than $90^{\circ}$ at the beginning and slowly decreases to acute angle. The reaction layer of titanium nitride is observed at the interface. In addition, the reaction of Ti in the braze and N in the bulk h-BN seemed to show diffusion limited spreading.

• Journal of Welding and Joining
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• v.16 no.2
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• pp.122-128
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• 1998

This investigation was performed to collect fundamental informations concerning the behavior of glass solders on ceramic joining process. The wettability of glasses on two types of alumina was evaluated by sessile drop method. SiO$_2$-CaO-Al$_2$O$_3$system glasses were selected as solder glasses, and alumina that have different purities were used for substrate materials. It is indicated that contact angles of glasses on 99% purity of alumina substrate do not change as increasing time at elevated temperature, however the contact angles on the 92% purity of alumina substrate exhibit the strong time dependency. The time-dependent property on 92% alumina was due to the interlayer reactions occurred between the glass solder and impurities on the substrate.

• Journal of Welding and Joining
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• v.20 no.3
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• pp.116-121
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• 2002

For the accumulation of a fundamental knowledge about the behavior of glass solder during the joining of ceramics, the wettability of solder on silicon nitride have been measured by sessile drop method. $SiO_2-MgO-Al_2O_3$ g1ass solder and oxynitride glass solders were selected as examples while silicon nitride which were used as substrates. Contact angle of solder on silicon nitride didn't decrease with time at high nitrogen content in the solder, but low nitrogen content in solders have the time-dependent property. Reason which contact angle of low nitrogen content in solders decrease on silicon nitride was that diffusion of nitrogen take place between solder and silicon nitride.

• Journal of ILASS-Korea
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• v.22 no.1
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• pp.36-41
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• 2017

The present study investigates the evaporation heat transfer characteristics of nanofluid droplet for different nanoparticle sizes. Also, the heat transfer coefficient was measured at different nanoparticle concentrations during evaporation. From the experimental results, it is found that the evaporation behavior of sessile droplet can be considered as constant radius mode due to pinning effect. The total evaporation time of sessile droplet decreases with nanoparticle size up to 7.9% for 0.10 vol% nanofluid droplet. As nanoparticle concentration increases, the clear difference in heat transfer coefficient is observed, showing that the size effect should be examined. This result would be helpful in designing the correlation between the nanoparticle size and the heat transfer characteristics for various applications.

• Korean Journal of Materials Research
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• v.18 no.1
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• pp.18-21
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• 2008

The wetting behavior of molten Fe on ${\alpha}-Al_2O_3$ single crystals with three different crystallographic orientations, $R(01\bar{1}2),\;A(11\bar{2}0),\;and\;C(0001)$, was investigated using the sessile drop method under a 10%$H_2-Ar$ atmosphere at 1873 K. It was found that the differences in the contact angle of the three differently oriented ${\alpha}-Al_2O_3$ single crystals were not significant (within $5^{\circ}$, which corresponded to the changes in the work of adhesion of $157mJ/m^2$) due to the surface reconstruction.

• Mycobiology
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• v.49 no.3
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• pp.213-222
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• 2021

Two new species of Fulvifomes are described from specimens collected in rainforests of Nonggang Nature Reserve of southern China, based on morphological characteristics and molecular phylogenetic analysis of the internal transcribed spacer (ITS) and nuclear large subunit ribosomal DNA (nLSU) sequences. Fulvifomes nonggangensis sp. nov. is characterized by perennial, sessile and solitary basidiocarps, applanate pileus, small cystidioles of 9.9-15.4 × 2.9-3.5 ㎛, large pores of 5-6 per mm, a dimitic hyphal system, and broadly ellipsoid basidiospores of 4.3-5.3 × 3.3-4.2 ㎛. F. tubogeneratus sp. nov. is characterized by perennial, sessile, and imbricate basidiocarps, a duplex context, small pores of 7-8 per mm, a dimitic hyphal system, and ovoid to subglobose basidiospores of 5.72 × 5.00 ㎛.

• Journal of ILASS-Korea
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• v.28 no.3
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• pp.113-118
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• 2023

This study investigates the evaporation characteristics of paired sessile droplets on a heated substrate. In particular, the evaporation time and contact line behaviors were analyzed based on the droplet-to-droplet distance and substrate temperature. The contact line behavior and volume variations were visualized using the shadowgraph method. It was observed that the contact diameter and contact angle exhibited similar behavior for both single and paired droplets regardless of the droplet-to-droplet distance and substrate temperature. The paired droplets demonstrated a longer evaporation time than the single droplet due to the vapor accumulation between the droplets. Furthermore, the scaled lifetime, defined as the ratio of evaporation time between paired and single droplets, increased as the droplet-to-droplet distance decreased and decreased as the substrate temperature increased, attributed natural convection.

• 대한치과보철학회:학술대회논문집
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• 2005.11a
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• pp.92-92
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• 2005

• Archives of Plastic Surgery
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• v.45 no.5
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• pp.411-417
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• 2018

Background Accessory auricles (AAs) are common congenital anomalies. We present a new classification according to location and shape, and propose a system for coding the classifications. Methods This study was conducted by reviewing the records of 502 patients who underwent surgery for AA. AAs were classified into three anatomical types: intraauricular, preauricular, and buccal. Intraauricular AAs were divided into three subtypes: intracrural, intratragal, and intralobal. Preauricular AAs were divided into five subtypes: precrural, superior pretragal, middle pretragal, inferior pretragal, and prelobal. Buccal AAs were divided into two subtypes: anterior buccal and posterior buccal. AAs were also classified according to their protrusion pattern above the surrounding surface: pedunculated, sessile, areolar, remnant, and depressed. Pedunculated and sessile AAs were subclassified as spherical, ovoid, lobed, and nodular, according to their body shape. Cartilage root presence and family history of AA were reviewed. A coding system for these classifications was also proposed. Results The total number of AAs in the 502 patients was 1,003. Among the locations, the superior pretragal subtype (27.6%) was the most common. Among the protrusion patterns and shapes, pedunculated ovoid AAs were the most common in the preauricular (27.8%) and buccal areas (28.0%), and sessile lobed AAs were the most common in the intraauricular area (48.7%). The proportion of AAs with a cartilage root was 78.4%, and 11% of patients had a family history. The most common type of preauricular AA was the superior pretragal pedunculated ovoid AA (13.2%) with a cartilage root. Conclusions This new system will serve as a guideline for classifying and coding AAs.

• Metals and materials international
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• v.24 no.6
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• pp.1241-1248
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• 2018

The reactive wetting behaviors of molten Zn-Al-Mg alloys on MnO- and amorphous (a-) $SiO_2$-covered steel sheets were investigated by the sessile drop method, as a function of the Al and Mg contents in the alloys. The sessile drop tests were carried out at $460^{\circ}C$ and the variation in the contact angles (${\theta}_c$) of alloys containing 0.2-2.5 wt% Al and 0-3.0 wt% Mg was monitored for 20 s. For all the alloys, the MnO-covered steel substrate exhibited reactive wetting whereas the $a-SiO_2$-covered steel exhibited nonreactive, nonwetting (${\theta}_c>90^{\circ}$) behavior. The MnO layer was rapidly removed by Al and Mg contained in the alloys. The wetting of the MnO-covered steel sheet significantly improved upon increasing the Mg content but decreased upon increasing the Al content, indicating that the surface tension of the alloy droplet is the main factor controlling its wettability. Although the reactions of Al and Mg in molten alloys with the $a-SiO_2$ layer were found to be sluggish, the wettability of Zn-Al-Mg alloys on the $a-SiO_2$ layer improved upon increasing the Al and Mg contents. These results suggest that the wetting of advanced high-strength steel sheets, the surface oxide layer of which consists of a mixture of MnO and $SiO_2$, with Zn-Al-Mg alloys could be most effectively improved by increasing the Mg content of the alloys.