scholarly journals Ultrasonication Technique: A Method for Dispersing Nanoclay in Wood Adhesives

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Alireza Kaboorani ◽  
Bernard Riedl ◽  
Pierre Blanchet
Keyword(s):  
Atomic Force Microscopy ◽  
Bond Strength ◽  
Polyvinyl Acetate ◽  
Shear Tests ◽  
Wood Adhesives ◽  
Force Microscopy ◽  
Block Shear ◽  
Atomic Force

The efficiency of ultrasonication technique to disperse nanoclay in polyvinyl acetate (PVA) was examined. A hydrophilic nanoclay was added to PVA, and its effects on bond strength of wood joints were determined. The results of bond strength measured on block shear tests showed that nanoclay increased the bond strength of wood joints, especially in humid conditions. Atomic force microscopy (AFM) proved that it can be used to examine the quality of nanoclay dispersion in a matrix very precisely. The results of this study showed that ultrasonication technique is efficient in mixing nanoclay with the PVA matrix.

scholarly journals The Infuence of Salicin on Rheological and Film-Forming Properties of Collagen

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1661
Author(s):  
Katarzyna Adamiak ◽  
Katarzyna Lewandowska ◽  
Alina Sionkowska
Keyword(s):  
Mechanical Properties ◽  
Atomic Force Microscopy ◽  
Infrared Spectroscopy ◽  
Rheological Properties ◽  
Silver Carp ◽  
Shear Tests ◽  
Force Microscopy ◽  
Atomic Force ◽  
Film Forming ◽  
Potential Applications

Collagen films are widely used as adhesives in medicine and cosmetology. However, its properties require modification. In this work, the influence of salicin on the properties of collagen solution and films was studied. Collagen was extracted from silver carp skin. The rheological properties of collagen solutions with and without salicin were characterized by steady shear tests. Thin collagen films were prepared by solvent evaporation. The structure of films was researched using infrared spectroscopy. The surface properties of films were investigated using Atomic Force Microscopy (AFM). Mechanical properties were measured as well. It was found that the addition of salicin modified the roughness of collagen films and their mechanical and rheological properties. The above-mentioned parameters are very important in potential applications of collagen films containing salicin.

Growth of GaN epilayers on Si(111) substrates using multiple buffer layers

2001 ◽  
Vol 693 ◽  
Author(s):  
P.R. Hageman ◽  
S. Haffouz ◽  
A. Grzegorczk ◽  
V. Kirilyuk ◽  
P.K. Larsen
Keyword(s):  
Atomic Force Microscopy ◽  
Epitaxial Films ◽  
Buffer Layers ◽  
High Quality ◽  
Nucleation Layer ◽  
Force Microscopy ◽  
Atomic Force ◽  
Intermediate Layers ◽  
Vapor Deposition Technique

AbstractWe present a study of the growth of high quality GaN films on Si(111) substrates by MetalOrganic Chemical Vapor Deposition technique. In order to improve the quality of the epitaxial films we introduced different nucleation or buffer layers and combinations of them. Our results obtained on an optimized AlN nucleation layer will serve as reference point. In order to improve the quality of the epitaxial films we introduced different combinations of nucleation and intermediate layers. The first combination consists of an optimized AlN nucleation layer followed by a 1 m-thick GaN film, on which we deposited SixNy/GaN intermediate layers. Based on the optimized AlN nucleation layer, we introduced AlGaN/GaN superlattices or AlN intermediate buffer layers. Additionally, we present results on the modification the Si(111) surface with NH3 to promote nucleation from selective GaN islands. In all experiments the total thickness of the GaN epilayers was 3 m m. X-ray diffraction, photoluminescence, Hall measurements and atomic force microscopy were used in order to elucidate the effectiveness of these growth processes. For the most successful deposition scheme, the one with the SixNy/GaN intermediate layers, the resulting GaN layers are of high quality as compared to the other methods. The donor bound exciton, which dominates the photoluminescence spectrum, showed a full width at half maximum (FWHM) of about 50 meV at room temperature and 10 meV at 4K. The FWHM of the symmetric (0002) rocking curves in w-scan is about 640 arcsec. The root-mean-square roughness, as measured by atomic force microscopy, does not exceed 10 Å.

scholarly journals Influence of sandblasting distance on enamel and ceramic structure bond strength

2014 ◽  
Vol 17 (2) ◽  
pp. 70 ◽  
Author(s):  
Lorena Rincon Garcia ◽  
Ana Cecilia Roso Reyes ◽  
Maria Isabel Canal ◽  
Mauricio Peña Castilho ◽  
Osnara Maria Mongruel Gomes ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Bond Strength ◽  
Aluminum Oxide ◽  
Third Molars ◽  
Ceramic Structure ◽  
Force Microscopy ◽  
Tukey Test ◽  
Atomic Force ◽  
Enamel Structure ◽  
One Way Anova

<p><strong>Objetive:</strong> The purpose of this study is was to evaluate the influence of sandblasting ceramic and enamel structure on bond strength, changing  distance.</p><p><strong>Material and methods:</strong> 60 third molars , were selected, enamel surfaces were ground flat with wet 600 - 2000 grit aluminum oxide abrasive papers  and polished with three, one, and one-fourth micrometer-grit diamond pastes. Obtained 120 lithium disilicate-based core ceramic discs ( 2 mm diameter;1 mm thickness), divided into 7 groups  [Group C, don’t sandblasting, Group SB-E(5-10) enamel sandblasting 5 and 10 mm, Group SB-C(5-10)  ceramic sandblasting 5 mm and 10 mm, Group SB-EC(5-10)  enamel and ceramic sandblasting 5 mm and 10 mm]   after was performed microshear and Atomic Force Microscopy (AFM), Statistic Teste of normality , after one-way ANOVA and Tukey test (α: 0.05).</p><p><strong>Results:</strong> The group C present bond strength (59.2±12.5), the group SB-E 5 mm (21.7±08.8) (p&lt;0.005), the group SB-E10 (53.6±14.3).</p><p><strong>Conclusion:</strong> The use of sandblasting treatment of the enamel surface a 5 mm by 20 seconds decreases the bonding strength to microshear.</p>

CVD Growth and Excimer Laser Processing of SiGe Alloys Monitored by Single Wavelength Ellipsometry and Atomic Force Microscopy

1997 ◽  
Vol 502 ◽  
Author(s):  
R. Larciprete ◽  
G. Padeletti ◽  
S. Cozzi ◽  
S. Pieretti
Keyword(s):  
Atomic Force Microscopy ◽  
Laser Processing ◽  
Growth Parameters ◽  
Laser Pulses ◽  
Force Microscopy ◽  
Atomic Force ◽  
Afm Analysis ◽  
Cvd Growth ◽  
Sample Irradiation

ABSTRACTSingle wavelength ellipsometry was used to monitor the CVD growth of Si(1-x)Gex alloys onSi and to evaluate the effect of sample irradiation by KrF laser pulses, performed during or afterthe CVD growth. The information obtained was correlated with AFM analysis results in order tooptimize the growth parameters for an improved morphological quality of the alloy layers.

scholarly journals Effect of Recasted Material Addition on the Quality of Metal-Ceramic Bond: A Macro-, Micro-, and Nanostudy

2018 ◽  
Vol 2018 ◽  
pp. 1-8
Author(s):  
Karolina Beer–Lech ◽  
Krzysztof Pałka ◽  
Anna Skic ◽  
Barbara Surowska ◽  
Krzysztof Gołacki
Keyword(s):  
Atomic Force Microscopy ◽  
Test Procedure ◽  
Bending Test ◽  
Force Microscopy ◽  
Atomic Force ◽  
Ceramic Bond ◽  
Metal Ceramic ◽  
Recycled Material ◽  
Sem Analyses

Using the recasted alloys in dental prosthetics could affect the quality of the metal-ceramic bond. However, scientists, alloys producers, and prosthetists are still of different opinions. The purpose of this study was to estimate the influence of recasting of the NiCrMo alloy on the metal-ceramic bond quality. The research was carried out on macro-, micro- and nanoscales using the three-point bending test procedure and hardness tests as well as atomic force microscopy and SEM analyses. The SEM analyses showed good integrity of the metal-ceramic bond. The τb index of all test samples was greater than 45 MPa. The highest values were recorded for the samples made of 50% and 100% of a brand new material. SEM analysis made after the bending test confirmed good metal-ceramic bond and exhibited adhesive-cohesive fracture. The largest hardness of metal plates was found for the samples containing 50% of the recycled material. Atomic force microscopy studies showed that the alloy containing 50% of the recycled material was characterized by the highest values of surface roughness parameters.

Crystal Growth of CdTe by Gradient Freeze in Universal Multizone Crystallizator (UMC)

2006 ◽  
Vol 508 ◽  
pp. 117-124 ◽  
Author(s):  
Ching Hua Su ◽  
Sandor L. Lehoczky ◽  
Chao Li ◽  
Balaji Raghothamachar ◽  
Michael Dudley ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Atomic Force Microscopy ◽  
Crystal Growth ◽  
Thermal History ◽  
Grown Crystal ◽  
X Ray ◽  
Hall Measurements ◽  
Force Microscopy ◽  
Atomic Force

In this study, crystals of CdTe were grown from melts, which have undergone different thermal history, by the unseeded gradient freeze method using the Universal Multizone Crystallizator (UMC). The effects of melt conditions on the quality of grown crystal were studied by various characterization techniques, including Synchrotron White Beam X-ray Topography (SWBXT), atomic force microscopy (AFM), electrical conductivity and Hall measurements.

scholarly journals Modification of FA0.85MA0.15Pb(I0.85Br0.15)3 Films by NH2-POSS

Crystals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1544
Author(s):  
Yangyang Zhang ◽  
Na Liu ◽  
Haipeng Xie ◽  
Jia Liu ◽  
Pan Yuan ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Photoelectron Spectroscopy ◽  
Spin Coating ◽  
Surface Composition ◽  
Morphological Changes ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Coating Method

The surface composition and morphology of FA0.85MA0.15Pb(I0.85Br0.15)3 films fabricated by the spin-coating method with different concentrations of NH2-POSS were investigated with atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), angle-resolved X-ray photoelectron spectroscopy (AR-XPS), and Fourier transform infrared spectroscopy (FTIR). It was found that the surface composition of the FA0.85MA0.15Pb(I0.85Br0.15)3 films was changed regularly through the interaction between NH2-POSS and the perovskite film. The corresponding surface morphological changes were also observed. When the concentration of NH2-POSS exceeded 10 mg/mL, a lot of cracks on the surface of the perovskite film were observed and the surface morphology was damaged. The surface composition and its distribution can be adjusted by changing the concentration of NH2-POSS and the proper concentration of NH2-POSS can substantially improve the quality of perovskite film.

scholarly journals High Mobility SiGe/Si n-MODFET Structures and Devices on Sapphire Substrates

2004 ◽  
Vol 809 ◽  
Author(s):  
Carl Mueller ◽  
Samuel Alterovitz ◽  
Edward Croke ◽  
George Ponchak
Keyword(s):  
Atomic Force Microscopy ◽  
Field Effect ◽  
Room Temperature ◽  
High Mobility ◽  
Force Microscopy ◽  
Si Substrates ◽  
Enhancement Mode ◽  
Sapphire Substrates ◽  
Atomic Force

ABSTRACTSiGe/Si n-type modulation doped field effect structures and transistors (n-MODFETs) have been fabricated on r-plane sapphire substrates. Mobilities as high as 1380 cm2/Vs were measured at room temperature. Excellent carrier confinement was shown by Shubnikov-de Haas measurements. Atomic force microscopy indicated smooth surfaces, with rms roughness less than 4 nm, similar to the quality of SiGe/Si n-MODFET structures made on Si substrates. Transistors with 2 μm gate lengths and 200 μm gate widths were fabricated and tested. An IDS of 9 mA was obtained by operating the transistor in an enhancement mode (positive VGS) and the maximum transconductance (gm) was 37 mS/mm at a VDS of 2.5 V. The transducer gain (Gt) measured with a loadpull system was 6.4 dB at 1 GHz for a VDS of 2.5 V and VGS=-0.4 V.

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