scholarly journals Biomaterials Screening Experiment Using Sessile Drop Contact Angles

2020 ◽  
Author(s):  
Lanny Griffin
Keyword(s):  
Sessile Drop ◽  
Contact Angles ◽  
Screening Experiment

scholarly journals Wetting ofAl2O3by Molten Aluminum: The Influence ofBaSO4Additions

2008 ◽  
Vol 2008 ◽  
pp. 1-12 ◽  
Author(s):  
Joaquin Aguilar-Santillan
Keyword(s):  
High Temperatures ◽  
Firing Temperature ◽  
Molten Aluminum ◽  
Sessile Drop ◽  
Contact Angles ◽  
Sessile Drop Technique ◽  
Pure Alumina ◽  
Two Temperatures ◽  
Drop Technique

The effects ofBaSO4additions on the wetting of alumina by molten aluminum were studied by the sessile drop technique. To study the effect ofBaSO4decomposition(1100–1150∘C), the additions were treated at two temperatures700∘C(973 K) and1450∘C(1723 K), respectively.BaSO4additions at low and high temperatures did not improve the nonwetting character of these compositions. However, at higher firing temperature, the formation ofBA6 (BaO•6Al2O3)has a nonwetting trend with increasing its content. To address theBA6specifically a pureBaO•6Al2O3was produced and tested. It was more nonwetting than the pure alumina. After the analysis of the contact angles for theBaSO4and theBA6 (BaO•6Al2O3), it was concluded that these additions to alumina do not inhibit wetting by molten aluminum. In fact, at the addition levels common for refractories, the wetting tendency of molten aluminum is enhanced. Alternative explanations for the effectiveness ofBaSO4additions to alumina refractories are discussed.

Comparative Study of Surface Energies of Native Oxides of Si(100) and Si(111) via Three Liquid Contact Angle Analysis

MRS Advances ◽  
2018 ◽  
Vol 3 (57-58) ◽  
pp. 3379-3390 ◽  
Author(s):  
Saaketh R. Narayan ◽  
Jack M. Day ◽  
Harshini L. Thinakaran ◽  
Nicole Herbots ◽  
Michelle E. Bertram ◽  
...  
Keyword(s):  
Contact Angle ◽  
Surface Energy ◽  
Sessile Drop ◽  
Surface Composition ◽  
Ion Beam ◽  
Contact Angles ◽  
Van Der Waals Interactions ◽  
Native Oxides ◽  
Relative Errors ◽  
Contact Angle Analysis

ABSTRACTThe effects of crystal orientation and doping on the surface energy, γT, of native oxides of Si(100) and Si(111) are measured via Three Liquid Contact Angle Analysis (3LCAA) to extract γT, while Ion Beam Analysis (IBA) is used to detect Oxygen. During 3LCAA, contact angles for three liquids are measured with photographs via the “Drop and Reflection Operative Program (DROP™). DROP™ removes subjectivity in image analysis, and yields reproducible contact angles within < ±1°. Unlike to the Sessile Drop Method, DROP can yield relative errors < 3% on sets of 20-30 drops. Native oxides on 5 x 1013 B/cm3 p- doped Si(100) wafers, as received in sealed, 25 wafer teflon boats continuously stored in Class 100/ISO 5 conditions at 24.5°C in 25% controlled humidity, are found to be hydrophilic. Their γT, 52.5 ± 1.5 mJ/m2, is reproducible between four boats from three sources, and 9% greater than γT of native oxides on n- doped Si(111), which averages 48.1 ± 1.6 mJ/m2 on four 4” Si(111) wafers. IBA combining 16O nuclear resonance with channeling detects 30% more oxygen on native oxides of Si(111) than Si(100). While γT should increase on thinner, more defective oxides, Lifshitz-Van der Waals interactions γLW on native oxides of Si(100) remain at 36 ± 0.4 mJ/m2, equal to γLW on Si(111), 36 ± 0.6 mJ/m2, since γLW arises from the same SiO2 molecules. Native oxides on 4.5 x 1018 B/cm3 p+ doped Si(100) yield a γT of 39 ± 1 mJ/m2, as they are thicker per IBA. In summary, 3LCAA and IBA can detect reproducibly and accurately, within a few %, changes in the surface energy of native oxides due to thickness and surface composition arising from doping or crystal structure, if conducted in well controlled clean room conditions for measurements and storage.

Wettability and Interfacial Characteristic of Sn-Ag-Cu Solder on Ni Substrates at Elevated Temperatures

2012 ◽  
Vol 554-556 ◽  
pp. 703-708
Author(s):  
Li Kun Zang ◽  
Zhang Fu Yuan Yuan ◽  
Hong Liang Yan ◽  
Xin Xue Li
Keyword(s):  
Integrated Circuits ◽  
Elevated Temperatures ◽  
Sessile Drop ◽  
Triple Line ◽  
Contact Angles ◽  
Sessile Drop Method ◽  
Reactive Wetting ◽  
Ni Substrate ◽  
Eds Analysis ◽  
Interfacial Characteristic

Wettability and interfacial characteristic of the Sn-3.0Ag-0.5Cu/Ni system are investigated by sessile drop method at the temperature range of 503~673K. The reactive wetting processes demonstrate that: contact angles between the solder and Ni substrate decrease as exponential decay and the equilibrium contact angles decrease monotonously with the temperature increasing. Triple-line mobility is enhanced as the temperature increases. Interface of the Sn-3.0Ag-0.5Cu /Ni interface are identified by EPMA and EDS analysis as (Cu,Ni)6Sn5 adjacent to the solder and Ni3Sn4 adjacent to the Ni substrate, respectively. Cu is condensed at the interface, the composition of (Cu,Ni)6Sn5 is (23.16~23.46)Ni- (36.56~37.52) Cu-(39.02~40.27)Sn (atom %). The formation of the (Cu,Ni)6Sn5 IMC was known to greatly improve the reliability of the solder joints in integrated circuits.

Reactive wetting of polycrystalline TiC by molten Zr55Cu30Al10Ni5 metallic glass alloy

2009 ◽  
Vol 24 (7) ◽  
pp. 2420-2427 ◽  
Author(s):  
Ping Shen ◽  
Qiaoli Lin ◽  
Qichuan Jiang ◽  
Hidetoshi Fujii ◽  
Kiyoshi Nogi
Keyword(s):  
Metallic Glass ◽  
Reaction Layer ◽  
Triple Junction ◽  
Sessile Drop ◽  
Contact Angles ◽  
Sessile Drop Method ◽  
The Other ◽  
Reactive Wetting ◽  
Exponential Functions ◽  
Glass Alloy

The isotherm wetting and spreading behaviors of polycrystalline TiC by molten Zr55Cu30Al10Ni5 alloy were investigated at 1133 to 1253 K in a vacuum by using a modified sessile drop method. The system displays good wettability with the initial and final stable contact angles of 44 to 50° and 10 to 14°, respectively, mildly depending on the temperature. The spreading kinetics follows well defined exponential functions and could be described by a molecular dynamic model. On the other hand, a ZrC reaction layer was formed at the interface. The wetting was primarily promoted by the Zr adsorption at the triple junction and then by the formation of the reaction layer.

scholarly journals Investigations on the Influence of Collagen Type on Physicochemical Properties of PVP/PVA Composites Enriched with Hydroxyapatite Developed for Biomedical Applications

Materials ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 37
Author(s):  
Magdalena Głąb ◽  
Anna Drabczyk ◽  
Sonia Kudłacik-Kramarczyk ◽  
Magdalena Kędzierska ◽  
Agnieszka Tomala ◽  
...  
Keyword(s):  
Physicochemical Properties ◽  
Bone Tissue ◽  
Tissue Regeneration ◽  
Sessile Drop ◽  
Average Molecular Weight ◽  
Contact Angles ◽  
Bone Tissue Regeneration ◽  
Poly Vinyl Alcohol ◽  
Swelling Properties ◽  
Application Potential

Nowadays, a great attention is directed into development of innovative multifunctional composites which may support bone tissue regeneration. This may be achieved by combining collagen and hydroxyapatite showing bioactivity, osteoconductivity and osteoinductivity with such biocompatible polymers as polyvinylpyrrolidone (PVP) and poly(vinyl alcohol) (PVA). Here PVA/PVP-based composites modified with hydroxyapatite (HAp, 10 wt.%) and collagen (30 wt.%) were obtained via UV radiation while two types of collagen were used (fish and bovine) and crosslinking agents differing in the average molecular weight. Next, their chemical structure was characterized using Fourier transform infrared (FT-IR) spectroscopy, roughness of their surfaces was determined using a stylus contact profilometer while their wettability was evaluated by a sessile drop method followed by the measurements of their surface free energy. Subsequently, swelling properties of composites were verified in simulated physiological liquids as well as the behavior of composites in these liquids by pH measurements. It was proved that collagen-modified composites showed higher swelling ability (even 25% more) compared to unmodified ones, surface roughness, biocompatibility towards simulated physiological liquids and hydrophilicity (contact angles lower than 90°). Considering physicochemical properties of developed materials and a possibility of the preparation of their various shapes and sizes, it may be concluded that developed materials showed great application potential for biomedical use, e.g., as materials filling bone defects supporting their treatments and promoting bone tissue regeneration due to the presence of hydroxyapatite with osteoinductive and osteoconductive properties.

scholarly journals Characterization of Rough PTFE Surfaces by the Modified Wilhelmy Balance Technique

Polymers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1528
Author(s):  
Christian W. Karl ◽  
Andrey E. Krauklis ◽  
Andrej Lang ◽  
Ulrich Giese
Keyword(s):  
Fractal Dimension ◽  
Sessile Drop ◽  
Contact Angle Hysteresis ◽  
Contact Angles ◽  
Polymer Surfaces ◽  
Counting Method ◽  
Balance Technique ◽  
Receding Contact ◽  
The Mean

The wetting of rough polymer surfaces is of great importance for many technical applications. In this paper, we demonstrate the relationship between the mean roughness values and the fractal dimension of rough and self-affine PTFE surfaces. We have used white light interferometry measurements to obtain information about the complex topography of the technical surfaces having different height distributions. Two different methods for the calculation of the fractal dimension were used: The height difference correlation function (HDC) and the cube counting method. It was demonstrated that the mean roughness value (Ra) correlates better with the fractal dimension Df determined by the cube counting method than with the Df values obtained from HDC calculations. However, the HDC values show a stronger dependency by changing the surface roughness. The advancing and receding contact angles as well as the contact angle hysteresis of PTFE samples of different roughness were studied by the modified Wilhelmy balance technique using deionized water as a liquid. The modified Wilhelmy balance technique enables the possibility for future analysis of very rough PTFE surfaces which are difficult to investigate with the sessile drop method.

scholarly journals Natural colloid mobilization and leaching in wettable and water repellent soil under saturated condition

2018 ◽  
Vol 66 (3) ◽  
pp. 271-278 ◽  
Author(s):  
Nasrollah Sepehrnia ◽  
Olga Fishkis ◽  
Bernd Huwe ◽  
Jörg Bachmann
Keyword(s):  
Organic Matter ◽  
Colloidal Particles ◽  
Sessile Drop ◽  
Organic Matter Content ◽  
Water Repellency ◽  
Contact Angles ◽  
Matter Content ◽  
Soil Horizon ◽  
Water Repellent ◽  
Coupled Transport

AbstractThe coupled transport of pollutants that are adsorbed to colloidal particles has always been a major topic for environmental sciences due to many unfavorable effects on soils and groundwater. This laboratory column study was conducted under saturated moisture conditions to compare the hydrophobic character of the suspended and mobilized colloids in the percolates released from a wettable subsoil and a water repellent topsoil. Both soils with different organic matter content were analyzed for wettability changes before and after leaching using sessile drop contact angles as well as water and ethanol sorptivity curves, summarized as repellency index. Hydrophobicity of the effluent suspensions was assessed using the C18 adsorption method. Water repellency level of the repellent soil decreased after leaching but remained on a lower level of water repellency, while, the wettable soil remained wettable. The leached colloids from the repellent soil were predominantly hydrophilic and the percentage of the hydrophobic colloid fraction in the effluent did not systematically changed with time. Total colloid release depended on soil carbon stock but not on soil wettability. Our results suggest that due to the respective character of transported colloids a similar co-transport mechanism for pollutants may occur which does not depend explicitly on soil wettability of the releasing horizon, but could be more affected by total SOM content. Further studies with a wider range of soils are necessary to determine if the dominant hydrophilic character of leached colloids is typical. Due to the mostly hydrophilic colloid character we conclude also that changes in wettability status, i.e. of wettable subsoil horizons due to the leachate, may not necessarily occur very fast, even when the overlaying topsoil is a repellent soil horizon with a high organic matter content.

Modeling of Sessile Droplet Evaporation on Engineered Surfaces

2019 ◽  
Vol 11 (6) ◽  
Author(s):  
Jyoti Prakash ◽  
Basant Singh Sikarwar
Keyword(s):  
Experimental Study ◽  
Relative Humidity ◽  
Evaporation Rate ◽  
Sessile Drop ◽  
Droplet Evaporation ◽  
Contact Angles ◽  
Surface Wettability ◽  
Aluminum Surface ◽  
Complex Nature ◽  
Wide Range

The evaporation of sessile drop has a wide range of application that includes printing, washing, cooling, and coating. Due to the complex nature of drop evaporation process, this phenomenon is reliant on several parameters such as ambiance and physiochemical properties of liquid and surface. In the present study, a mathematical model of water droplet evaporation on an engineered aluminum surface is developed. Experimental study is carried out for the validation of code. The data obtained from the simulation is validated against the data obtained from an experimental study as well as the data available in the literature and good agreement was found among them. Post-validation, the effect of surface wettability and environment conditions on a droplet evaporation rate is estimated. It is inferred from the outcomes that the temperature at the apex of the drop varies linearly with the increasing relative humidity. Droplet volume has a significant impact on the evaporation rate and comparatively higher evaporative flux for a smaller volume of the drop with large contact angles. This unveils the possibility of achieving the required evaporation rate by controlling surface wettability and relative humidity conditions near the drop.

scholarly journals Effect of Oxygen Inhibition Layer of Universal Adhesives on Enamel Bond Fatigue Durability and Interfacial Characteristics With Different Etching Modes

2017 ◽  
Vol 42 (6) ◽  
pp. 636-645 ◽  
Author(s):  
H Ouchi ◽  
A Tsujimoto ◽  
K Nojiri ◽  
K Hirai ◽  
T Takamizawa ◽  
...  
Keyword(s):  
Sessile Drop ◽  
Contact Angles ◽  
Inhibition Layer ◽  
Universal Adhesive ◽  
Water Contact ◽  
Oxygen Inhibition ◽  
Fatigue Durability ◽  
Shear Fatigue ◽  
Universal Adhesives ◽  
Interfacial Characteristics

SUMMARY Objective: The purpose of this study was to evaluate the effect of the oxygen inhibition layer of universal adhesive on enamel bond fatigue durability and interfacial characteristics with different etching modes. Methods: The three universal adhesives used were Scotchbond Universal Adhesive (3M ESPE, St Paul, MN, USA), Adhese Universal (Ivoclar Vivadent, Schaan, Lichtenstein), and G-Premio Bond (GC, Tokyo, Japan). The initial shear bond strength and shear fatigue strength to enamel was determined in the presence and absence of the oxygen inhibition layer, with and without phosphoric acid pre-etching. The water contact angle was also measured in all groups using the sessile drop method. Results: The enamel bonding specimens with an oxygen inhibition layer showed significantly higher (p&lt;0.05) initial shear bond strengths and shear fatigue strengths than those without, regardless of the adhesive type and etching mode. Moreover, the water contact angles on the specimens with an oxygen inhibition layer were significantly lower (p&lt;0.05) than on those without, regardless of etching mode. Conclusion: The results of this study suggest that the oxygen inhibition layer of universal adhesives significantly increases the enamel bond fatigue durability and greatly changes interfacial characteristics, suggesting that the bond fatigue durability and interfacial characteristics of these adhesives strongly rely on its presence.

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