Papers by Keyword: Wettability

Abstract: This paper studied wettability of water strider’s typical part, contact angle of water strider’s leg, abdomen, back and wing was measured by the contact angle measuring instrumen, which were 161.5°,156.3°,157.6°and 156.4°respectively, they showed superhydrophobic. Microstructure of water strider’s leg, abdomen, back and wing was observed through scanning electron microscopy, It found that 4 typical parts of water strider are composite structure of micron scale and nano-scale, although their forms is different, they have reached the super-hydrophobic effect.

Abstract: In order to improve the properties of a co-extruded wood-plastic composite (WPC), different types of cellulosic fibres, pulp cellulose (PC), a combination of PC/microfibrillated cellulose (MFC) and wood flour (WF) with different size were introduced into shell layer based on a polypropylene (PP) matrix. The combination of PC/MFC improved the tensile properties compared to PC alone; but the impact strength was independent on the MFCs content. The presence of MFCs did not influence the water absorption (WA), but thickness swelling (TS) increased, however. The properties of the WF/PP-shell composite were highly affected by the WF particle size. The 20-mesh-sized WF-loaded composite had weaker mechanical properties compared to the smaller sized, Arbocel C320, shell-layer filled WPC. Also, Arbocel C320/PP-coated WPC had the highest tensile properties among all studied composites. The morphology of the composites was examined with a scan electron microscope.

Abstract: Regarding the application of enhanced oil recovery (EOR), reservoir heterogeneity leads to early water breakthrough and significant water production, so that substantial cost may be needed to treat the produced water. Gel treatments have been widely used to prevent early water breakthrough and great amount of water production by the modification of permeability. Reservoir wettability gives significant impact on gel treatment. This study is to assess the effect of wettability on the reservoir performance during gel treatment in layered heterogeneous reservoirs. Performances were compared in terms of water-oil ratio and cumulative oil recovery for different wettability conditions. With respect to oil recovery, there is no striking improvement by gel treatment. However, the results indicate that gel process presents 77% decrement of water-oil ratio over waterflood for oil-wet system and 51% for water-wet system. Gel is distributed in reservoir more widely for oil-wet conditions than water-wet conditions, which means the effect of gels is more dominant in oil-wet conditions rather than water-wet conditions.

Abstract: The effects of flux components and compositions of solder alloys on the wettability of the Sn-Zn alloys on aluminum surface was investigated. The results show that the wettability of the Sn-9Zn solder on aluminum substrate improved with flux of double solvents composed of diethanolamine and triethanolamine, which is better than single solvent. When flux is composed of 3% zinc fluoborate as activator and 30% triethanolamine plus 67% diethanolamine as double solvents, the spreading area of the Sn-9Zn solder reaches to 75%. Trace addition (0.002%-0.005%) of Al results in significant improvement of the wettability of the Sn-9Zn based solder. However, additions of Bi or Sb are not beneficial to the wettability of the solder on aluminum substrate.

Abstract: We investigated the growth and structure properties of C-Mg thin films obtained for the first time by Thermionic Vacuum Arc (TVA) deposition. The TVA technology is suitable for producing nanostructured materials because of the high power density of the vapor plasma generated by accelerated electron flux from the cathode and high energy of the ions incident on the depositing film, both these properties ensuring a high dispersion of the evaporated material. The properties of the deposited C-Mg thin films were investigated in terms of wettability and morphology. The surface free energy (SFE) was determined by means of Surface Energy Evaluation System (See System) indicating a hydrophobic character and the morphology were determined from BF-TEM image performed by Philips CM 120 ST TEM system.

Abstract: When teeming rare earth treated steels the nozzle blockage occurred so frequently that seriously interferes the application of RE in steels. In this study we tried to investigate the relationship between the wettablility of 16MnRE steel and nozzle materials. The results showed that the weakest wettability of steel liquid was observed on fused silica among the six nozzle materials. Next came zircon and high-alumina nozzle. It has no obvious difference between the 16MnRE steels when final deoxidized containing and not containing Al addition. The wettability of 10Ti steel was weaker than 16MnRE steels on zircon nozzle. The clay nozzle was corroded by the precipitate from steel liquid.

Abstract: A mathematic model based on moving mesh Arbitrary Lagrange-Eulerian (ALE) is developed to solve incompressible fluid flow concerned with the free surface and wettability. A mercury sessile drop with different wetting angles is chosen to validate this method. Besides, two more extensive applications called electrowetting-on-dielectric (EWOD) and transferred drop are numerically simulated and compared with previous researchers work in order to demonstrate its efficiency.

Abstract: The purpose of this work was to study the wettability of single-walled carbon nanotube (SWCNTs) and molten 96.5Sn-3.0Ag-0.5Cu (SAC305) lead-free solder alloy. The SWCNTs was coated with silver (Ag) by using an electroless plating method in order to enhance its wettability. The wetting behavior of molten SAC305 alloy on three different substrates, alumina, un-coated SWCNTs and Ag-coated SWCNTs was investigated by employing a modified sessile drop technique. The wetting angle between the molten SAC305 and the three substrates was measured at temperature range of 250-550 °C. The average wetting angles between the molten SAC305 and the alumina, the un-coated SWCNTs and the Ag-coated SWCNTs substrates were 130.7±1.3°, 128.4±4.2° and 120.1±3.5°, respectively. The wettabilty of the SWCNTs was improved by coating it with silver. The wetting angle of the Ag-coated SWCNTs was decreased approx. 9° compared to that of the un-coated. Increasing temperature has slightly affected on the wettability of SWCNTs and the molten SAC305.

Abstract: Zn-Al filler metal wettability tests were performed on pure aluminum surface. The test results show the spreading area of Zn-Al filler metal gets large on pure aluminum surface gradually with the increase of Al content in Zn-Al filler metal under the match of CsF-AlF₃ flux. When Al content in the Zn-Al filler metal is 15 wt.%, the spreading area of 85Zn-15Al filler metal is biggest on pure aluminum surface. Accordingly, the dendritic eutectoid structure size is smaller near the interface between the Zn-Al filler metal and the pure aluminum base metal by metallographic analysis. When Al content in the Zn-Al filler metal exceeds 15wt.%, the spreading area of filler metal begins to become small. At the same time, the eutectoid structure presents circle shape near the interface between the Zn-Al filler metal and the pure aluminum base metal.

Abstract: Three coals (Jincheng coal, Hancheng coal and Shan-bei coal) varying widely in coal type have been treated with anionic surfactant Sodium Dodecyl Sulphate (SDS). The effect of SDS on wettability of coals was explored by contact angles and zeta potentials characterisation techniques. Results obtained show that the addition of SDS can obviously improve the wettability of coals, and as the coal rank decreases, the wettability increases under investigation. Moreover, the wettability obviously increases with the significant decrease of particle size. The zeta potential for each coal, in the absence of surfactant, is negative, and the potential becomes more negative with the addition of SDS. Meanwhile, the FTIR spectrogram was used to test the changes of-COOH and-OH to analyze the reason for change of wettability, the results show that the wettability changes may be attributed to that the negative active ions of SDS are adsorbed on the coal surface, resulting in the increase of hydrophilic groups of the coal surface.