Characterizing the Surface Roughness of Thermomechanical Pulp Fibers with Atomic Force Microscopy

Holzforschung ◽  
2001 ◽  
Vol 55 (5) ◽  
pp. 511-520 ◽  
Author(s):  
Rebecca Snell ◽  
Leslie H. Groom ◽  
Timothy G. Rials
Keyword(s):  
Surface Roughness ◽  
Loblolly Pine ◽  
Thermomechanical Pulp ◽  
Fiber Types ◽  
Pulp Fibers ◽  
Sem Images ◽  
Apparent Increase ◽  
Force Microscopy ◽  
Atomic Force ◽  
Scanning Electron

Summary Loblolly pine, separated into mature and juvenile portions, was refined at various pressures (4, 8 and 12 bar). Fiber surfaces were investigated using a Scanning Electron Microscope (SEM) and an Atomic Force Microscope (AFM). Refiner pressure had a significant effect on the fiber surfaces. SEM images showed an apparent increase in surface roughness with increased refiner pressure. This was shown quantitatively with data from the AFM that was analyzed using 5, 2.5 and 1.25 μm scan sizes. A scan size of 2.5 μm was found to be the most informative in terms of quantifying the effect of the different treatments on the two fiber types. The calculated surface roughness was greatest at 8 bar for both wood types. Juvenile fibers in general had higher surface roughness values than mature fibers. The results suggest that refining pressure may influence the failure mechanism of juvenile and mature wood differently.

scholarly journals Comparison of the Enamel Surface Roughness from Different Polishing Methods: Scanning Electron Microscopy and Atomic Force Microscopy Investigation

2020 ◽  
Vol 14 (02) ◽  
pp. 299-305
Author(s):  
Kiatanan Sugsompian ◽  
Ratchawan Tansalarak ◽  
Thosapol Piyapattamin
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Surface Roughness ◽  
Atomic Force Microscopy ◽  
Enamel Surface ◽  
Similar Data ◽  
Force Microscopy ◽  
Atomic Force ◽  
Significant Difference ◽  
Scanning Electron

Abstract Objective This study aimed to compare the enamel surface roughness created by four polishing methods after debonding, by using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Materials and Methods Four experimental polishing groups (Sof-Lex disc, SD; sandblaster, SB; tungsten carbide bur, TB; and white stone bur, WB) and one control group were selected from 100 premolars (n = 20/group). The experimental teeth were bonded with a bracket, thermocycled, and debonded. Residual adhesive was removed by either of the respective methods. Pre and postdebonding root mean square (Rq) values were obtained from AFM evaluations. All specimens were examined and evaluated with SEM using a modified enamel surface index (modified ESI). Statistical Analysis Differences among the polishing methods were compared with analysis of variance and Fisher’s least significant difference test at p < 0.05. Results Both microscopic evaluations indicated that the surface with the greatest roughness herein belonged to the SD group, followed by that for SB, TB, and WB groups. AFM measurements indicated a maximum postdebonding Rq herein for the WB group and a significantly greater surface roughness for the TB and WB groups than for the SD and SB groups. Among the experimental groups, SEM followed by modified ESI evaluations revealed similar data to those obtained with AFM. Significant differences were seen among all paired groups, except for that between the SB and TB groups. Conclusion Within the limitations of this study, all four polishing methods were concluded to be clinically acceptable for removing residual orthodontic adhesives.

A Scanning Electron and Atomic Force Microscopy Study of the Surface Morphology and Composition of CsI Films as Affected by Evaporation Rate and Humid-Air Exposure

2005 ◽  
Vol 11 (2) ◽  
pp. 124-132 ◽  
Author(s):  
Giorgio S. Senesi ◽  
Mariangela A. Nitti ◽  
Antonio Valentini
Keyword(s):  
Surface Roughness ◽  
Atomic Force Microscopy ◽  
Surface Morphology ◽  
Slow Rate ◽  
Evaporation Rate ◽  
Humid Air ◽  
Air Exposure ◽  
Force Microscopy ◽  
Atomic Force ◽  
Scanning Electron

Evaporation rate and subsequent exposure to humid air affect the surface morphology and composition of cesium iodide (CsI) films and, in turn, their photoemissive efficiency when used as photocathodes. The surface morphology and elemental composition of 300-nm-thick CsI films grown at two different rates (1 nm/s and 0.04 nm/s), both freshly evaporated and after 24-h exposure to humid air were investigated by means of atomic force microscopy and scanning electron microscopy/electron diffraction spectroscopy. The CsI film freshly evaporated at a slow rate exhibited a granular surface presenting circular holes or craters where the CsI material was moved from the center to the boundaries. After 24-h exposure to humid air, this film coalesced in large grain showing a marked increase of surface roughness. Conversely, the CsI film grown at a fast rate mostly retained its original surface uniformity and homogeneity with no presence of holes and craters after 24-h exposure to humid air. Further, surface roughness and average peak height decreased, but the surface coalesced in large grains spaced by small fractures where the CsI coverage was almost lost. In conclusion, the films grown at a fast evaporation rate were affected by 24-h exposure to humid air less than those grown at a slow rate, and are thus expected to possess a greater long-term stability.

Hydroxyapatite Coating Influenced by Ti6Al4V Substrate Roughness

2015 ◽  
Vol 638 ◽  
pp. 62-66
Author(s):  
Florin Constantinescu ◽  
Robert Ciocoiu ◽  
Octavian Trante ◽  
Ion Ciucă
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Surface Roughness ◽  
Crystal Morphology ◽  
Crystal Shape ◽  
Substrate Roughness ◽  
Force Microscopy ◽  
Atomic Force ◽  
Mean Size ◽  
Scanning Electron

In this paper the author’s main goal was to determine if the roughness of the substrate (a Ti6Al4V alloy) shows any influence on the hydroxyapatite (HA) crystal morphology and distribution. Disks of Ti6Al4V, 24mm in diameter and 1mm thickness are sandblasted with Al2O3particles with different mean size: 29, 45 and 110μm. The disks are analyzed prior coating by atomic force microscopy (AFM) to determine the surface roughness. The samples are then cleaned and coated with HA by immersion in a solution derived from [Ca (NO3)2.4H2O] and P2O5dissolved in ethylene glycol – the process was repeated 3 times. The coated samples are analyzed by scanning electron microscopy (SEM) to observe HA crystal shape, size and distribution.

AFM Study on the Surface Dissolution of Hydroxyapatite

2007 ◽  
Vol 336-338 ◽  
pp. 1553-1555 ◽  
Author(s):  
Dong Seok Seo ◽  
Hwan Kim ◽  
Jong Kook Lee
Keyword(s):  
Surface Roughness ◽  
Immersion Time ◽  
Distilled Water ◽  
Force Microscopy ◽  
Atomic Force ◽  
Hydroxyapatite Powder ◽  
Hydroxyapatite Ceramics ◽  
Initial Stage ◽  
Moisture Protection ◽  
Scanning Electron

The surface dissolution of hydroxyapatite ceramics in distilled water was investigated by using atomic force microscopy (AFM) and scanning electron microscopy (SEM). The disks made of hydroxyapatite powder were sintered at 1200oC for 2 h in air with under moisture protection. After sintering, the disks were polished to smoothness using 1 μm diamond and they were soaked in 40 ml of pH 7.4 distilled water at 37oC for certain period of time. The morphological change of hydroxyapatite surface, specifically at the initial stage of immersion, and related surface roughness were observed with immersion time. The present study suggested that an artificial fact like surface scratch in this case initiated to be eliminated prior to the surface dissolution along grain boundary. That is, the surface roughness decreased at the initial stage of immersion, and then increased due to the surface dissolution.

Surface roughness measurements of vanadium-contaminated fluidized cracking catalysts by atomic force microscopy

1996 ◽  
Vol 54 ◽  
pp. 866-867
Author(s):  
H. Kinney ◽  
M.L. Occelli ◽  
S.A.C. Gould
Keyword(s):  
Surface Roughness ◽  
Zeolite Y ◽  
Atomic Level ◽  
Microporous Structure ◽  
Contact Mode ◽  
Force Microscopy ◽  
Atomic Force ◽  
Before And After ◽  
Roughness Measurements ◽  
Cracking Catalysts

For this study we have used a contact mode atomic force microscope (AFM) to study to topography of fluidized cracking catalysts (FCC), before and after contamination with 5% vanadium. We selected the AFM because of its ability to well characterize the surface roughness of materials down to the atomic level. It is believed that the cracking in the FCCs occurs mainly on the catalysts top 10-15 μm suggesting that the surface corrugation could play a key role in the FCCs microactivity properties. To test this hypothesis, we chose vanadium as a contaminate because this metal is capable of irreversibly destroying the FCC crystallinity as well as it microporous structure. In addition, we wanted to examine the extent to which steaming affects the vanadium contaminated FCC. Using the AFM, we measured the surface roughness of FCCs, before and after contamination and after steaming.We obtained our FCC (GRZ-1) from Davison. The FCC is generated so that it contains and estimated 35% rare earth exchaged zeolite Y, 50% kaolin and 15% binder.

Brittle Behaviour in Aspirin Crystals: Evidence of Spalling Fracture

2020 ◽  
Author(s):  
Benjamin P. A. Gabriele ◽  
Craig J. Williams ◽  
Douglas Stauffer ◽  
Brian Derby ◽  
Aurora J. Cruz-Cabeza
Keyword(s):  
Surface Roughness ◽  
Atomic Force Microscopy ◽  
Single Crystals ◽  
Spalling Fracture ◽  
Force Microscopy ◽  
Atomic Force ◽  
Afm Imaging

<div> <div> <div> <p>Single crystals of aspirin form I were cleaved and indented on their dominant face. Upon inspection, it was possible to observe strongly anisotropic shallow lateral cracks due to the extreme low surface roughness after cleavage. Atomic Force Microscopy (AFM) imaging showed spalling fractures nucleating from the indent corners, forming terraces with a height of one or two interplanar spacings d100. The formation of such spalling fractures in aspirin was rationalised using basic calculations of attachment energies, showing how (100) layers are poorly bonded when compared to their relatively higher intralayer bonding. An attempt at explaining the preferential propagation of these fractures along the [010] direction is discussed. </p> </div> </div> </div>

Brittle Behaviour in Aspirin Crystals: Evidence of Spalling Fracture

2020 ◽  
Author(s):  
Benjamin P. A. Gabriele ◽  
Craig J. Williams ◽  
Douglas Stauffer ◽  
Brian Derby ◽  
Aurora J. Cruz-Cabeza
Keyword(s):  
Surface Roughness ◽  
Atomic Force Microscopy ◽  
Single Crystals ◽  
Spalling Fracture ◽  
Force Microscopy ◽  
Atomic Force ◽  
Afm Imaging

<div> <div> <div> <p>Single crystals of aspirin form I were cleaved and indented on their dominant face. Upon inspection, it was possible to observe strongly anisotropic shallow lateral cracks due to the extreme low surface roughness after cleavage. Atomic Force Microscopy (AFM) imaging showed spalling fractures nucleating from the indent corners, forming terraces with a height of one or two interplanar spacings d100. The formation of such spalling fractures in aspirin was rationalised using basic calculations of attachment energies, showing how (100) layers are poorly bonded when compared to their relatively higher intralayer bonding. An attempt at explaining the preferential propagation of these fractures along the [010] direction is discussed. </p> </div> </div> </div>

Etching Treatment Effect on Surface Morphology of Dental Structures

2017 ◽  
Vol 68 (11) ◽  
pp. 2700-2703 ◽  
Author(s):  
Kamel Earar ◽  
Vasile Iulian Antoniac ◽  
Sorana Baciu ◽  
Simion Bran ◽  
Florin Onisor ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Surface Morphology ◽  
Phosphoric Acid ◽  
Human Teeth ◽  
Strong Bond ◽  
Force Microscopy ◽  
Atomic Force ◽  
Human Dentine ◽  
Dental Surface ◽  
Scanning Electron

This study examined and compared surface of human dentine after acidic etching with hydrogen peroxide, phosphoric acid liquid and gel. Surface demineralization of dentin is necessary for a strong bond of adhesive at dental surface. Split human teeth were used. After application of mentioned substances at dentin level measures of the contact angle and surface morphology were employed. Surface morphology was analyzed with the help of scanning electron microscopy and atomic force microscopy. Liquid phosphoric acid yielded highest demineralization showing better hydrophobicity than the rest, thus having more contact surface. Surface roughness are less evident and formed surface micropores of 4 �m remained open after wash and air dry providing better adhesive canalicular penetration and subsequent bond.

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