Investigating the Effect of Hydrophilic Surface Modification on Droplet Evaporation

In this study, surface modification of stainless steel flat plates was performed using nanoscale bilayers assembly method to increase the surface’s hydrophilicity and enhance evaporation. Thin layers of SiO2 nanoparticles layered onto the stainless steel surfaces were used to modify their surface properties, and the relationship between the number of layers (0~20) and water’s hydrophilicity (surface tension) was investigated. The effects of modification on evaporation were then tested using de-ionized water. According to experimental results, surface modification was able to reduce the contact angle of water on stainless steel flat plate from the unmodified 87o to 7o at 18 layers, significantly increasing the hydrophilicity of the surface. Evaporation experiments show that the evaporation heat transfer enhancement for droplets on stainless steel plates is at least 300%.Keywords: bilayers assembly, hydrophilicity, surface modification, evaporation performance

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Investigating the use of Nanoscale Bilayers Assembly on Stainless Steel Plate to Improve Evaporation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.395-396.718 ◽

2013 ◽

Vol 395-396 ◽

pp. 718-725 ◽

Cited By ~ 2

Author(s):

Shen Chun Wu ◽

Dawn Wang ◽

Hsih Shing Li ◽

Sin Jie Lin ◽

Chao Tsai Hsu ◽

...

Keyword(s):

Contact Angle ◽

Stainless Steel ◽

Surface Modification ◽

Contact Angles ◽

Steel Plates ◽

Stainless Steel Surface ◽

Hydrophilic Surface ◽

Evaporation Time ◽

Assembly Technique ◽

The Relationship

This study investigated the use of nanoscale bilayers assembly film for hydrophilic surface modification on stainless steel plates and observed its effects on the evaporation of acetone and ethanol on the plates. This study first established the nanoscale bilayers assembly technique, and then performed hydrophilic surface modification on stainless steel plates by changing the surface structure, producing different contact angles. The relationship between the number of bilayers (10, 20, and 30) and the resulting contact angle was empirically determined; results indicated that 20-bilayer modification yielded the best result, reducing the contact angle from 70° (unmodified surface) to 12°. Beyond 20 bilayers, at 30 bilayers, the samples show no significant changes or improvements to contact angle or hydrophilicity. Results from evaporation time tests showed that, compared to the evaporation time of ethanol and acetone on unmodified flat stainless steel surface, this decreased contact angle can improve the evaporation time by 100%, clearly indicating that hydrophilic surface modifications causes significant improvement in evaporation.

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Investigating the Use of Nanoscale Bilayers Assembly on Stainless Steel Plate for Surface Hydrophilic Modification

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.401-403.792 ◽

2013 ◽

Vol 401-403 ◽

pp. 792-795 ◽

Cited By ~ 2

Author(s):

Shen Chun Wu ◽

Dawn Wang ◽

Sin Jie Lin ◽

Pin Wun Ciou ◽

Chen Yu Chung ◽

...

Keyword(s):

Contact Angle ◽

Stainless Steel ◽

Surface Modification ◽

Steel Plate ◽

Optimal Number ◽

Hydrophilic Surface ◽

Stainless Steel Plate ◽

Hydrophilic Modification ◽

Assembly Method ◽

The Relationship

This study investigated the use of nanoscale bilayers assembly for hydrophilic surface modification on stainless steel plate. This study first performed nanoscale bilayers assembly method, with the addition of top layer coatings for durability purposes, to modify the surface structure and thereby the hydrophilicity of the surface at 15, 17, 20, 23, and 25 bilayers. The relationship between the number of bilayers and the resulting contact angle was then empirically established. Results showed 17 bilayers to be the optimal number of bilayers among the samples tested, resulting in the smallest contact angle of 11° (compared to 70° on unmodified surface), corresponding to the highest surface wettability and hydrophilicity. From 0 to 17 bilayers, the contact angle seems to decrease linearly with the number of bilayers. Beyond 17 bilayers, at 20, 23, 25, and 30 bilayers, the samples showed no significant improvements in contact angle or hydrophilicity.

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Layer-by-layer coating of stainless steel plates mediated by surface priming treatment to improve antithrombogenic properties

Biomedical Science and Engineering ◽

10.4081/bse.2016.22 ◽

2016 ◽

Author(s):

Irene Carmagnola ◽

Tiziana Nardo ◽

Francesca Boccafoschi ◽

Valeria Chiono

Keyword(s):

Stainless Steel ◽

Surface Modification ◽

Platelet Activation ◽

Colorimetric Assay ◽

Thrombus Formation ◽

Human Platelets ◽

Steel Plates ◽

Blue Dye ◽

Layer By Layer

The stainless steel (SS) stents have been used in clinics since 1994. However, typical drawbacks are restenosis and thrombus formation due to limited endothelialisation and hemocompatibility. Surface modification is a smart strategy to enhance antithrombogenicity by promoting endothelialisation. In this work, the layer-by-layer (LbL) technique was applied for coating SS model substrates, after surface priming by functionalisation with 3-aminopropyl triethoxysilane (APTES). A LbL coating made of 14 layers of poly(styrene sulfonate)/poly(diallyldimethylammonium chloride) and heparin as last layer was deposited. FTIR-ATR analysis and contact angle measurements showed that LbL was an effective method to prepare nanostructured coatings. XPS analysis and colorimetric assay employing 1,9-dimethylmethylene blue dye to detect -COOH groups confirmed the successful polyelectrolyte deposition on the coated samples. Preliminary in vitro cell tests, using whole blood and human platelets, were performed to evaluate how surface modification affects platelet activation. Results showed that SS and SS-APTES surfaces induced platelet activation, as indicated by platelet spreading and filopodia formation. After surface modification by LbL coating, the platelets assumed a round shape and no fibrin nets were detected. Data demonstrated that LbL coating is a promising technique to fabricate antithrombogenic surface.

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Improved Quantitative Recovery of Listeria monocytogenes from Stainless Steel Surfaces Using a One-Ply Composite Tissue

Journal of Food Protection ◽

10.4315/0362-028x-67.10.2212 ◽

2004 ◽

Vol 67 (10) ◽

pp. 2212-2217 ◽

Cited By ~ 41

Author(s):

KEITH L. VORST ◽

EWEN C. D. TODD ◽

ELLIOT T. RYSER

Keyword(s):

Stainless Steel ◽

Phosphate Buffer ◽

Phosphate Buffer Solution ◽

Steel Plates ◽

Stainless Steel Surface ◽

Disc Diffusion ◽

Buffer Solution ◽

Composite Tissue ◽

Steel Surfaces ◽

Diffusion Assay

Four sampling devices, a sterile environmental sponge (ES), a sterile cotton-tipped swab (CS), a sterile calcium alginate fiber-tipped swab (CAS), and a one-ply composite tissue (CT), were evaluated for quantitative recovery of Listeria monocytogenes from a food-grade stainless steel surface. Sterile 304-grade stainless steel plates (6 by 6 cm) were inoculated with approximately 106 CFU/cm2 L. monocytogenes strain Scott A and dried for 1 h. The ES and CT sampling devices were rehydrated in phosphate buffer solution. After plate swabbing, ES and CT were placed in 40 ml of phosphate buffer solution, stomached for 1 min and hand massaged for 30 s. Each CS and CAS device was rehydrated in 0.1% peptone before swabbing. After swabbing, CS and CAS were vortexed in 0.1% peptone for 1 min. Samples were spiral plated on modified Oxford agar with modified Oxford agar Rodac Contact plates used to recover any remaining cells from the stainless steel surface. Potential inhibition from CT was examined in both phosphate buffer solution and in a modified disc-diffusion assay. Recovery was 2.70, 1.34, and 0.62 log greater using CT compared with ES, CS, and CAS, respectively, with these differences statistically significant (P < 0.001) for ES and CT and for CAS, CS, and CT (P < 0.05). Rodac plates were typically overgrown following ES, positive after CS and CAS, and negative after CT sampling. CT was noninhibitory in both phosphate buffer solution and the modified disc-diffusion assay. Using scanning electron microscopy, Listeria cells were observed on stainless steel plates sampled with each sampling device except CT. The CT device, which is inexpensive and easy to use, represents a major improvement over other methods in quantifying L. monocytogenes on stainless steel surfaces and is likely applicable to enrichment of environmental samples.

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ICE ADHESION

Canadian Journal of Physics ◽

10.1139/p62-138 ◽

1962 ◽

Vol 40 (10) ◽

pp. 1294-1309 ◽

Cited By ~ 43

Author(s):

H. H. G. Jellinek

Keyword(s):

Stainless Steel ◽

Adhesive Strength ◽

Viscosity Coefficient ◽

Interfacial Free Energy ◽

Steel Plates ◽

Shear Tests ◽

Viscosity Coefficients ◽

Water Films ◽

Yield Values ◽

Steel Surfaces

Results of shear tests for the system ice – stainless steel and ice – optically flat fused quartz as a function of the rate of shear and roughness of the steel surfaces are presented. The adhesive strength decreased with decreasing roughness of steel surfaces, and the force versus time curves for smooth steel plates resembled those of two solids sliding over each other with a liquid layer between them. This behavior was especially evident in the case of the optically flat quartz. The adhesive strength as a function of rate of shear was linear for both ice – stainless steel and ice – quartz but there were indications of yield values. The results agree with the assumption of a liquidlike layer on ice. Ratios of viscosity coefficient to layer thickness were evaluated for both systems, and viscosity coefficients are estimated. Shear experiments on thin water films between glass plates support the assumption of a liquidlike layer on ice. The importance of interfacial free energy considerations is pointed out.

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Pool Boiling Inversion and Hysteresis with Femtosecond Laser Processed 304 Stainless Steel Surfaces for Heat Transfer Enhancement

2020 19th IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITherm) ◽

10.1109/itherm45881.2020.9190948 ◽

2020 ◽

Author(s):

Justin Costa-Greger ◽

Alfred Tsubaki ◽

Josh Gerdes ◽

Mark Anderson ◽

Craig Zuhlke ◽

...

Keyword(s):

Heat Transfer ◽

Stainless Steel ◽

Femtosecond Laser ◽

Heat Transfer Enhancement ◽

Pool Boiling ◽

304 Stainless Steel ◽

Transfer Enhancement ◽

Steel Surfaces

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Modification of Stainless Steel Surfaces by Ion Beams for Improved Corrosion Resistance

MRS Proceedings ◽

10.1557/proc-93-361 ◽

1987 ◽

Vol 93 ◽

Author(s):

R. S. Bhattacharya ◽

C. N. Raffoul ◽

A. K. Rai ◽

P. P. Pronko

Keyword(s):

Stainless Steel ◽

Corrosion Behavior ◽

Potentiodynamic Polarization ◽

Ion Beam ◽

Electron Beam Evaporation ◽

Thin Layers ◽

304 Stainless Steel ◽

Stainless Steel 304 ◽

Modified Surfaces ◽

Steel Surfaces

ABSTRACTAn investigation of the ion beam mixing of Mo and Ta layers with 304 stainless steel and the potentiodynamic polarization behavior of the modified surfaces are described.Alternating thin layers (<100Å) of stainless steel (304) and either Mo or Ta were deposited by electron beam evaporation. Ion mixing was performed with 2 MeV Ni+ at a fluence of 5 × 1016cm−2. Examination of the mixed surfaces with TEN revealed characteristics of the amorphous phase and in some cases being embedded with crystalline regions for both Mo and Ta mixed stainless steel surfaces. The amorphous surfaces were tested for their corrosion behavior in 1M H2SO4 and O.1M NaCl solutions by the potentiodynamic polarization method. Significantly improved corrosion behavior were obtained for modified surfaces compared to unmodified stainless steel.

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