Effect of surface roughness on the spectral and total emittance of platinum

Surface sealants are reported to ensure surface smoothness and improve the surface quality of composite restorations. These sealants should also reduce the bacterial adhesion on composite surfaces however, there is not much information regarding their performance on bulk-fill composite materials. The aim of this study was to evaluate the effect of surface sealant application on surface roughness and bacterial adhesion of various restorative materials. Disc-shaped samples were prepared from a compomer, a conventional composite and three bulk-fill composites. Specimens of each group were divided into two groups (n = 9): with/without surface sealant (Biscover LV, [BLV]). Surface roughness values were examined by profilometry and two samples of each group were examined for bacterial adhesion on a confocal laser scanning microscope (CLSM). Bacterial counts were calculated by both broth cultivation and microscopic images. Results were analyzed with one-way ANOVA and Bonferroni/Dunn tests. Following the BLV application, there was a decrease in the surface roughness values of all groups however, only Tetric N-Ceram Bulk and Beautifil-Bulk groups showed significantly smoother surfaces (p < 0.001). There were no significant differences among material groups without BLV application. Evaluating bacterial adhesion after BLV application, conventional composite had the lowest values among all followed by the compomer group. Beautifil-Bulk had significantly the highest bacterial adhesion (p < 0.05), followed by Tetric N-Ceram Bulk group. Without BLV application, there was no significant difference among bacterial adhesion values of groups (p > 0.05). CLSM images showed cell viability in groups. Bulk-fill composites showed higher bacterial adhesion than conventional composite and compomer materials. The surface sealant was found to be highly effective in lowering bacterial adhesion, but not so superior in smoothing the surfaces of restorative materials. So, surface sealants could be used on the restorations of patients with high caries risk.

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Effect of surface roughness on couple stress squeeze film lubrication of long porous partial journal bearings

Industrial Lubrication and Tribology ◽

10.1108/00368790610670764 ◽

2006 ◽

Vol 58 (4) ◽

pp. 176-186 ◽

Cited By ~ 5

Author(s):

N.M. Bujurke ◽

N.B. Naduvinamani ◽

Syeda Tasneem Fathima ◽

S.S. Benchalli

Keyword(s):

Surface Roughness ◽

Couple Stress ◽

Journal Bearings ◽

Squeeze Film ◽

Film Lubrication ◽

Effect Of Surface

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Effect of Surface Roughness on Pool Boiling Heat Transfer of Water on a Superhydrophilic Aluminum Surface

Journal of Heat Transfer ◽

10.1115/1.4036599 ◽

2017 ◽

Vol 139 (10) ◽

Cited By ~ 25

Author(s):

Jinsub Kim ◽

Seongchul Jun ◽

Jungho Lee ◽

Juan Godinez ◽

Seung M. You

Keyword(s):

Heat Transfer ◽

Surface Roughness ◽

Boiling Heat Transfer ◽

Aluminum Surface ◽

Transfer Coefficients ◽

Copper Surfaces ◽

Heat Transfer Coefficients ◽

Superhydrophilic Surface ◽

Aluminum Surfaces ◽

Effect Of Surface

The effect of surface roughness on the pool boiling heat transfer of water was investigated on superhydrophilic aluminum surfaces. The formation of nanoscale protrusions on the aluminum surface was confirmed after immersing it in boiling water, which modified surface wettability to form a superhydrophilic surface. The effect of surface roughness was examined at different average roughness (Ra) values ranging from 0.11 to 2.93 μm. The boiling heat transfer coefficients increased with an increase in roughness owing to the increased number of cavities. However, the superhydrophilic aluminum surfaces exhibited degradation of the heat transfer coefficients when compared with copper surfaces owing to the flooding of promising cavities. The superhydrophilic aluminum surfaces exhibited a higher critical heat flux (CHF) than the copper surfaces. The CHF was 1650 kW/m2 for Ra = 0.11 μm, and it increased to 2150 kW/m2 for Ra = 0.35 μm. Surface roughness is considered to affect CHF as it improves the capillary wicking on the superhydrophilic surface. However, further increase in surface roughness above 0.35 μm did not augment the CHF, even at Ra = 2.93 μm. This upper limit of the CHF appears to result from the hydrodynamic limit on the superhydrophilic surface, because the roughest surface with Ra = 2.93 μm still showed a faster liquid spreading speed.

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Effect of Surface Roughness on Slip Resistance of Rubber

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.189-193.1538 ◽

2011 ◽

Vol 189-193 ◽

pp. 1538-1542

Author(s):

Li Xiao Jia ◽

Yong Zhen Zhang ◽

Yong Ping Niu ◽

San Ming Du ◽

Jian Li

Keyword(s):

Surface Roughness ◽

Correlation Coefficient ◽

Correlation Coefficients ◽

Roughness Parameters ◽

Test Conditions ◽

Slip Resistance ◽

Materials Used ◽

Almost All ◽

Effect Of Surface

In order to decrease accidents of slips and falls, COFs of rubber samples with different surface roughness were measured by Brungraber Mark II. And the correlation coefficients between roughness parameters and COF were calculated. The rusults have shown that the COF increases with surface roughness and the correlation coefficient between Sq and COF is highest. In general, almost all the roughness parameters used in the study have high correlation with COF. Parameters had the highest correlation with COF depends on the materials used and test conditions.

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