Hydrophilization of corn seeds by non-equilibrium gaseous plasma

AbstractPlasma agriculture is a promising niche of interdisciplinary research where the physics, of non-equilibrium gases meets surface chemistry and biological responses. Despite numerous scientific papers, the interaction of gaseous plasma with seeds is not understood enough to make the technique useful in practical agriculture. An obstacle is an improper methodology adopted by different authors. In this paper, we show that the surface wettability does not depend on discharge parameters such as power and pressure, but rather on the fluence of oxygen atoms onto the seed surface. The proper methodology is demonstrated for the case of corn seeds. The surface activation, which enables improved water uptake or good adhesion of a coating, progresses relatively linearly up to the O-atom fluence of 3 × 1024 m−3 and remains constant thereafter. The minimal water contact angle achievable using oxygen plasma treatment is a few degrees.

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Surface Modification of 3D-Poly(glycerol-sebacate)/ Poly(L-lactic-acid) Porous Scaffolds by Oxygen Plasma Enhances Proliferation and Differentiation of Goat Temporomandibular Joint Disc Cells

Journal of Biomaterials and Tissue Engineering ◽

10.1166/jbt.2019.2208 ◽

2019 ◽

Vol 9 (12) ◽

pp. 1653-1661

Author(s):

Tiandong Cao ◽

Fangrui Dong ◽

Pengfei Zhang ◽

Jingying Liu ◽

Zhe Xing ◽

...

Keyword(s):

Lactic Acid ◽

Plasma Treatment ◽

Temporomandibular Joint ◽

Oxygen Plasma ◽

Collagen Type ◽

Collagen Type I ◽

Oxygen Plasma Treatment ◽

Porous Scaffolds ◽

Type I ◽

Water Contact

3D poly(glycerol-sebacate)/poly(L-lactic-acid) (PGS/PLLA) scaffolds, produced by thermally induced phase separation (TIPS) method were treated with oxygen plasma in order to reduce the hydrophobicity of the PGS/PLLA membranes. After the oxygen plasma treatment, the pore size of scaffolds became uniform as well as an increasing in the roughness of the surface. No influence on chemical characteristics such as composition and bond types of PLLA was detected after the treatment. However, the change in the ratio of the scaffold elements before and after the oxygen plasma treatment was detected. Oxygen plasma treatment reduced the average of water contact angle of the TIPS film from 103.7± 10.1 to 64.7± 12.6 at the maximum exposure time (970 s) and power (100 W). The results showed that the goat temporomandibular joint (TMJ) cells attached well to the surface of the oxygen plasma modified scaffold. Furthermore, this modification significantly enhanced cell viability, increased cell proliferation and expression of related genes (Collagen type I mRNA and Collagen type II mRNA). The results demonstrated that it is a promising modification method to promote applications of PGS/PLLA based scaffolds to the regeneration of TMJ discs.

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Shear Bond Strength of Ceramic Veneers to Zirconia–Calcium Silicate Cores

Coatings ◽

10.3390/coatings11111326 ◽

2021 ◽

Vol 11 (11) ◽

pp. 1326

Author(s):

Ting-Yi Chiang ◽

Chun-Chuan Yang ◽

Yi-Hsuan Chen ◽

Min Yan ◽

Shinn-Jyh Ding

Keyword(s):

Contact Angle ◽

Phase Composition ◽

Surface Morphology ◽

Bond Strength ◽

Plasma Treatment ◽

Calcium Silicate ◽

Shear Bond Strength ◽

Oxygen Plasma ◽

Oxygen Plasma Treatment ◽

Water Contact

Improving the bond strength of veneering ceramics to ZrO2-based cores remains a challenge. The purpose of this study was to evaluate the shear bond strength of different ZrO2 cores containing calcium silicate (CaSi) to veneering ceramics. Five types of ZrO2-based cores (n = 230) were divided into two groups: with or without oxygen plasma treatment. These were bound to two veneering ceramics (IPS e.max Ceram or VITA VM9). Shear bond strength of veneering ceramics to various cores was measured (n = 10), in addition to phase composition, surface morphology and contact angle of the cores. The results indicated that the plasma treatment had a significant effect on the water contact angle of the ZrO2-based cores, but had little effect on the bond strength. Regardless of plasma treatment, the highest strength value was recorded in the ZrO2 core specimen containing 20 wt % CaSi, when all cores were adhered to VITA VM 9 veneer. When using IPS e.max Ceram veneer, the shear bond strength of the plasma-treated 20 wt % CaSi-containing ZrO2 core was 16.6 ± 0.9 MPa higher than that of VITA In-Ceram YZ core control (13.4 ± 1.0 MPa) (p < 0.05). We conclude that the presence of 20 wt % CaSi in ZrO2 can improve the shear bond strength of zirconia-based cores to veneering ceramic.

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Effect of Oxygen Plasma Treatment on Bacterial Cellulose-Alginate Composite Sponge as a Yeast Cell Carrier for Ethanol Fermentation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.724-725.1150 ◽

2013 ◽

Vol 724-725 ◽

pp. 1150-1153

Author(s):

Suchata Kirdponpattara ◽

Bi-Min Zhang Newby ◽

Muenduen K.M. Phisalaphong

Keyword(s):

Plasma Treatment ◽

Bacterial Cellulose ◽

Ethanol Fermentation ◽

Oxygen Plasma ◽

Yeast Cells ◽

Oxygen Plasma Treatment ◽

Immobilized Cell ◽

Water Contact ◽

Cell Carrier ◽

Significant Difference

A bacterial cellulose-alginate composite sponge (BCA) was developed for use as a cell carrier in ethanol fermentation. Its hydrophilicity was improved by oxygen plasma treatment. Due to the etching effect in plasma application, the external surface roughness of treated BCA was increased, resulting in a decrease of advancing water contact angle. However, oxygen plasma treatment might not be able to create sufficient hydrophilic functional groups on the internal pore surface of BCA, where the yeast cells would be immobilized during fermentation. As a result, under batch fermentation, no significant difference in ethanol production obtained from the immobilized cell systems using the treated and untreated BCAs.

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Surface Modification of Chitosan Membranes by Oxygen Plasma Treatment

Materials Science Forum ◽

10.4028/www.scientific.net/msf.610-613.1259 ◽

2009 ◽

Vol 610-613 ◽

pp. 1259-1262 ◽

Cited By ~ 4

Author(s):

Na Ru Zhao ◽

Ying Jun Wang ◽

Li Ren ◽

Xiao Feng Chen

Keyword(s):

Contact Angle ◽

Plasma Treatment ◽

Water Contact Angle ◽

Photoelectron Spectroscopy ◽

Oxygen Plasma ◽

Chamber Pressure ◽

Oxygen Plasma Treatment ◽

Water Contact ◽

Plasma Irradiation ◽

Chitosan Membranes

Chitosan membranes were prepared by solvent cast method. In order to increase cell adhesion of the chitosan membranes, oxygen plasma treatment was applied to improve the hydrophilicity of the surface of chitosan membranes. The surface properties were characterized by scanning electron microscopy (SEM), contact angle analyzer, X-ray photoelectron spectroscopy (XPS). The effects of exposure time, plasma generating power, and chamber pressure on water contact angle of the chitosan membranes were investigated. The water contact angle of chitosan membranes decreased from 94.1° to 49.2° after plasma treatment. Which suggested the surfaces became more hydrophilic. XPS analysis showed that the oxygen content and the ratio of O/C increased markedly after oxygen plasma treatment. Furthermore, it was found that C-H bonds were broken with oxygen plasma treatment. C-OH group had been increased after plasma irradiation.

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High Breakdown Voltage GaN HEMT Device Fabricated on Self-Standing GaN Substrate

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.347-350.1535 ◽

2013 ◽

Vol 347-350 ◽

pp. 1535-1539

Author(s):

Jian Jun Zhou ◽

Liang Li ◽

Hai Yan Lu ◽

Ceng Kong ◽

Yue Chan Kong ◽

...

Keyword(s):

Plasma Treatment ◽

Breakdown Voltage ◽

Oxygen Plasma ◽

Cutoff Frequency ◽

Chemical Vapor ◽

Current Gain ◽

Organic Chemical ◽

Oxygen Plasma Treatment ◽

Gan Hemt ◽

High Breakdown Voltage

In this letter, a high breakdown voltage GaN HEMT device fabricated on semi-insulating self-standing GaN substrate is presented. High quality AlGaN/GaN epilayer was grown on self-standing GaN substrate by metal organic chemical vapor deposition. A 0.8μm gate length GaN HEMT device was fabricated with oxygen plasma treatment. By using oxygen plasma treatment, gate forward working voltage is increased, and a breakdown voltage of more than 170V is demonstrated. The measured maximum drain current of the device is larger than 700 mA/mm at 4V gate bias voltage. The maximum transconductance of the device is 162 mS/mm. In addition, high frequency performance of the GaN HEMT device is also obtained. The current gain cutoff frequency and power gain cutoff frequency are 19.7 GHz and 32.8 GHz, respectively. A high fT-LG product of 15.76 GHzμm indicating that homoepitaxy technology is helpful to improve the frequency performance of the device.

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On the Effectiveness of Oxygen Plasma and Alkali Surface Treatments to Modify the Properties of Polylactic Acid Scaffolds

Polymers ◽

10.3390/polym13101643 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1643

Author(s):

Ricardo Donate ◽

María Elena Alemán-Domínguez ◽

Mario Monzón

Keyword(s):

Surface Properties ◽

Enzymatic Degradation ◽

Oxygen Plasma ◽

Physicochemical Characterization ◽

Surface Treatments ◽

Carboxyl Groups ◽

Scanning Calorimetry ◽

Water Contact ◽

Angle Measurements ◽

3D Printed

Surface modification of 3D-printed PLA structures is a major issue in terms of increasing the biofunctionality and expanding the tissue engineering applications of these parts. In this paper, different exposure times were used for low-pressure oxygen plasma applied to PLA 3D-printed scaffolds. Alkali surface treatments were also evaluated, aiming to compare the modifications introduced on the surface properties by each strategy. Surface-treated samples were characterized through the quantification of carboxyl groups, energy-dispersive X-ray spectroscopy, water contact angle measurements, and differential scanning calorimetry analysis. The change in the surface properties was studied over a two-week period. In addition, an enzymatic degradation analysis was carried out to evaluate the effect of the surface treatments on the degradation profile of the 3D structures. The physicochemical characterization results suggest different mechanism pathways for each type of treatment. Alkali-treated scaffolds showed a higher concentration of carboxyl groups on their surface, which enhanced the enzymatic degradation rate, but were also proven to be more aggressive towards 3D-printed structures. In contrast, the application of the plasma treatments led to an increased hydrophilicity of the PLA surface without affecting the bulk properties. However, the changes on the properties were less steady over time.

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An Assessment of Surface Treatments for Adhesion of Polyimide Thin Films

Polymers ◽

10.3390/polym13121955 ◽

2021 ◽

Vol 13 (12) ◽

pp. 1955

Author(s):

Marco Cen-Puc ◽

Andreas Schander ◽

Minerva G. Vargas Gleason ◽

Walter Lang

Keyword(s):

Flexible Electronics ◽

Oxygen Plasma ◽

Reactive Ion Etching ◽

Peel Test ◽

Scratch Test ◽

Peel Strength ◽

Surface Treatments ◽

Oxygen Plasma Treatment ◽

Polyimide Films ◽

Ion Etching

Polyimide films are currently of great interest for the development of flexible electronics and sensors. In order to ensure a proper integration with other materials and PI itself, some sort of surface modification is required. In this work, microwave oxygen plasma, reactive ion etching oxygen plasma, combination of KOH and HCl solutions, and polyethylenimine solution were used as surface treatments of PI films. Treatments were compared to find the best method to promote the adhesion between two polyimide films. The first selection of the treatment conditions for each method was based on changes in the contact angle with deionized water. Afterward, further qualitative (scratch test) and a quantitative adhesion assessment (peel test) were performed. Both scratch test and peel strength indicated that oxygen plasma treatment using reactive ion etching equipment is the most promising approach for promoting the adhesion between polyimide films.

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