Estimation of the surface area of etching layer on platinum alloy catalyst gauzes using microscopy images

The purpose of this study was to investigate the combined effect of mechanical and chemical treatments on the shear bond strength (SBS) of metal orthodontic brackets on zirconia restoration. The zirconia specimens were randomly divided into 12 groups (n=10) according to three factors: AL (Al2O3) and CO (CoJet™) by sandblasting material; SIL (silane), ZPP (Zirconia Prime Plus), and SBU (Single Bond Universal) by primer; and N (not thermocycled) and T (thermocycled). The specimens were evaluated for shear bond strength, and the fractured surfaces were observed using a stereomicroscope. Scanning electron microscopy images were also obtained. CO-SBU combination had the highest bond strength after thermocycling (26.2 MPa). CO-SIL showed significantly higher SBS than AL-SIL (p<0.05). CO-ZPP resulted in lower bond strength than AL-ZPP before thermocycling, but the SBS increased after thermocycling (p>0.05). Modified Adhesive Remnant Index (ARI) scoring and SEM figures were consistent with the results of the surface treatments. In conclusion, CO-SBU, which combines the effect of increased surface area and chemical bonding with both 10-MDP and silane, showed the highest SBS. Sandblasting with either material improved the mechanical bonding by increasing the surface area, and all primers showed clinically acceptable increase of shear bond strength for orthodontic treatment.

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Kinetics of oxygen reduction reaction on nanostructured thin-film platinum alloy catalyst

Journal of Power Sources ◽

10.1016/j.jpowsour.2012.04.077 ◽

2012 ◽

Vol 215 ◽

pp. 77-88 ◽

Cited By ~ 16

Author(s):

R.K. Ahluwalia ◽

X. Wang ◽

A. Lajunen ◽

A.J. Steinbach ◽

S.M. Hendricks ◽

...

Keyword(s):

Thin Film ◽

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Reduction Reaction ◽

Platinum Alloy ◽

Nanostructured Thin Film ◽

Kinetics Of ◽

Alloy Catalyst

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Preparation and Characterization of Green Porous Palm Shell Based Activated Carbon by Two Step Chemical Activation Using KOH

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.773-774.1127 ◽

2015 ◽

Vol 773-774 ◽

pp. 1127-1132 ◽

Cited By ~ 4

Author(s):

Abdurrahman Garba ◽

Hatijah Basri ◽

Noor Shawal Nasri

Keyword(s):

Activated Carbon ◽

Surface Area ◽

Palm Oil ◽

Organic Contaminants ◽

Agricultural Waste ◽

Chemical Activation ◽

Bet Surface Area ◽

Water And Wastewater ◽

Microscopy Images

The large quantity of agricultural waste materials that poses disposal challenge to our environment could be converted into useful products such as activated carbon (AC). Palm oil shell based porous AC was prepared by two step process using KOH as the chemical activant. Palm oil shell was carbonized at 800°C for 2 hours and activated using CO2 at same temperature for 1 hour which yield 23.27% fixed carbon. The AC was characterized by Langmuir surface area, BET surface area and pore volume of 410.7 m2/g, 350 m2/g and 0.2 cm3/g respectively, the FTIR analysis identified the presence of alkanes, carbonyls and hydroxyls as the main functional groups in the AC. Scanning electron microscopy images illustrates the gradual formation of pores from the precursor to the produced AC due to elimination of volatiles and contaminants in the material. However, the AC produced showed basic properties suitable for the removal of hydrophobic organic contaminants in water and wastewater.

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