Artificially aged spruce and beech wood surfaces reactivated using FE-DBD atmospheric plasma

Abstract Although weathering is usually carried out in outdoor conditions, even ageing in indoor conditions can cause significant changes to wood surfaces. We found these to notably impact wetting and coatability of surfaces of common beech (Fagus sylvatica L.) and Norway spruce [Picea abies (L.) Karst.] wood. These effects were well overcome and the surfaces reactivated using a novel kind of a plasma device. On both kinds of wood, ageing caused significant changes in their colour, opening of pits and cell wall destruction. Infrared spectra indicated a significant decrease of aromatic lignin and production of non-conjugated carbonyl groups. Surface free energies and spreading kinetics varied much upon this kind of ageing. In beech, pull-off strengths for a commercial waterborne wood coating slightly decreased for longer exposure times. For the reactivation of wood surfaces, we employed a novel approach using a floating electrode dielectric barrier discharge (FE-DBD) plasma, which had not been done on wood before. Similar to other plasma techniques, the surface free energy (SFE) increased after treatment. On beech wood, the plasma treatment (PT) led to higher pull-off strengths of the waterborne coating. On spruce wood, the coating mostly showed cohesive failures after ageing, and thus the PTs showed less improvements.

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Low-Dose Cold Atmospheric Plasma Promoting Schwann Cells Proliferation By Activating PI3K/Akt/mTOR Pathway

10.21203/rs.3.rs-598902/v1 ◽

2021 ◽

Author(s):

Bibo Ge ◽

Jie Bao ◽

Jinwu Chen ◽

Xinzhong Xu ◽

Juehua Jing ◽

...

Keyword(s):

Cell Cycle ◽

Schwann Cells ◽

Low Dose ◽

Treatment Time ◽

Mtor Pathway ◽

Atmospheric Plasma ◽

Control Group ◽

Dbd Plasma ◽

Cold Atmospheric Plasma ◽

Plasma Device

Abstract Cold atmospheric plasma (CAP) is an emerging technology that has attracted the attention of many researchers in many fields and disciplines. In this study, a dielectric barrier discharge (DBD) plasma device was used to treat Schwann cells (SCs) cultured in vitro, and the effect of CAP on SCs proliferation was evaluated by cell morphology, cell viability, cell cycle and expression of related proteins in SCs. The results showed that the production of intracellular ROS and RNS increased with the increase of CAP treatment time. Compared with the control group, the proliferation of SCs treated with CAP for less than 14 s significantly increased, and and then gradually decreased. Besides, the cell cycle results also showed that more cells were in the S+G2/M phase at this time.The PI3K/Akt/mTOR pathway was activated by low-dose CAP, and the expression of cyclinD1 was consistent with the trend of cell proliferation. In addition, n-acetyl-L-cysteine (NAC) preconditioning significantly prevented CAP-induced cellular changes. In conclusion, low-dose CAP-induced of SCs proliferation was closely related to the PI3K/Akt/mTOR signaling pathway. This study provides a new idea for the treatment of peripheral nerve injury.

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Deposition of Zinc Oxide Coatings on Wood Surfaces Using the Solution Precursor Plasma Spraying Process

Coatings ◽

10.3390/coatings11020183 ◽

2021 ◽

Vol 11 (2) ◽

pp. 183

Author(s):

Ghiath Jnido ◽

Gisela Ohms ◽

Wolfgang Viöl

Keyword(s):

Zinc Oxide ◽

Ftir Spectroscopy ◽

Photoelectron Spectroscopy ◽

Color Change ◽

Uv Light ◽

Beech Wood ◽

Nitrate Solution ◽

Ftir Spectra ◽

Solution Precursor ◽

Wood Surfaces

In the present work, the solution precursor plasma spray (SPPS) process was used to deposit zinc oxide (ZnO) coatings on wood surfaces using zinc nitrate solution as precursor to improve the hydrophobicity and the color stability of European beech wood under exposure to ultraviolet (UV) light. The surface morphology and topography of the wood samples and the coatings were characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The formation of ZnO was detected with the help of X-ray photoelectron spectroscopy (XPS) and by Fourier transform infrared (FTIR) spectroscopy. The FTIR spectra of the coated samples showed the typical Zn–O band at 445 cm−1. According to the XPS analysis, the coatings consist of two different Zn-containing species: ZnO and Zn(OH)2. Variation of the deposition parameters showed that the most significant parameters affecting the microstructure of the coating were the solution concentration, the deposition scan speed, and carrier gas flow rate. The wettability behaviors of the coated wood were evaluated by measuring the water contact angle (WCA). The coatings that completely covered the wood substrates showed hydrophobic behaviors. UV-protection of wood surfaces after an artificial UV light irradiation was evaluated by color measurements and FTIR spectroscopy. The ZnO-coated wood surfaces were more resistant to color change during UV radiation exposure. The total color change decreased up to 60%. Additionally, the FTIR spectra showed that the wood surfaces coated with ZnO had more stability. The carbonyl groups formation and C=C-bonds consumption were significantly lower.

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Treatment of wood with atmospheric plasma discharge: study of the treatment process, dynamic wettability and interactions with a waterborne coating

Holzforschung ◽

10.1515/hf-2020-0182 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Jure Žigon ◽

Matjaž Pavlič ◽

Pierre Kibleur ◽

Jan Van den Bulcke ◽

Marko Petrič ◽

...

Keyword(s):

Plasma Treatment ◽

Treatment Process ◽

Beech Wood ◽

Treated Wood ◽

Plasma Discharge ◽

Contact Angles ◽

Atmospheric Plasma ◽

Waterborne Coating ◽

Spruce Wood ◽

The Impact

AbstractPlasma treatment is becoming a mature technique for modification of surfaces of various materials, including wood. A better insight in the treatment process and the impact of the plasma on properties of wood bulk are still needed. The study was performed on Norway spruce and common beech wood, as well as their thermally modified variations. The formations of the airborne discharge, as well as mass changes of the treated wood, were monitored. The impact of such treatment on wood-coating interaction was investigated by evaluating the dynamic wettability and penetration into wood. At the wood surface, plasma streamers were observed more intense on denser latewood regions. Wood mass loss was higher with increasing number of passes through the plasma discharge and was lower for thermally modified wood than for unmodified wood. Plasma treatment increased the surface free energy of all wood species and lowered the contact angles of a waterborne coating, these together indicating enhanced wettability after treatment. Finally, the distribution and penetration depth of the coating were studied with X-ray microtomography. It was found that the coating penetrated deeper into beech than into spruce wood. However, the treatment with plasma increased the penetration of the coating only into spruce wood.

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Development of a portable cold atmospheric plasma device for infected wound management

2017 Medical Technologies National Congress (TIPTEKNO) ◽

10.1109/tiptekno.2017.8238066 ◽

2017 ◽

Author(s):

Yusuf Hakan Usta ◽

Utku Kursat Ercan

Keyword(s):

Atmospheric Plasma ◽

Wound Management ◽

Infected Wound ◽

Cold Atmospheric Plasma ◽

Plasma Device

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Colour stability of surface finishes on thermally modified beech wood

Annals of WULS, Forestry and Wood Technology ◽

10.5604/01.3001.0015.2391 ◽

2021 ◽

Vol 114 ◽

pp. 116-124

Author(s):

Gabriela Slabejová ◽

MÁRIA ŠMIDRIAKOVÁ

Keyword(s):

Surface Finish ◽

Beech Wood ◽

Surface Finishing ◽

Colour Stability ◽

Colour Difference ◽

Surface Finishes ◽

Before And After ◽

Thermally Modified Wood ◽

Wood Surfaces ◽

Modified Wood

Colour stability of surface finishes on thermally modified beech wood. The paper deals with the influence of the type of transparent surface finish on the change of colour of the surfaces of native beech wood and thermally modified wood. At the same time, the colour stability of three surface finishes on the surfaces of native and thermally modified beech wood was monitored. Beech wood was thermally modified at temperature of 125 °C for 6 hours. The thermal treatment was performed in a pressure autoclave APDZ 240, by the company Sundermann s.r.o in Banská Štiavnica. Three various types of surface finishes (synthetic, wax-oil, water-based) were applied onto the wood surfaces. The colour of the surfaces of native wood and thermally modified wood was measured in the system CIELab before and after surface finishing; the coordinates L*, a*, b*, C*ab and h*ab were measured. From the coordinates measured before and after surface finishing, the differences were calculated and then the colour difference ∆E* was calculated. Subsequently, the test specimens with the surface finishes were exposed to natural sunlight, behind glass in the interior for 60 days. The surface colour was measured at specified time of the exposure (10, 20, 30, 60 days). The results showed that the colour of the wood surfaces changed after application of the individual surface finishes; and the colour difference reached a change visible with a medium quality filter up to a high colour difference. The wax-oil surface finish caused a high colour difference on native wood and on thermally modified wood as well. On native beech wood, the lowest colour difference after exposure to sunlight was noticeable on the synthetic surface finish. On the surface of wood thermally modified, after exposure to sunlight, the lowest colour difference was noticeable on the surface with no surface finish.

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Prospective, Comparative Clinical Pilot Study of Cold Atmospheric Plasma Device in the Treatment of Atopic Dermatitis

10.21203/rs.3.rs-453127/v1 ◽

2021 ◽

Author(s):

Young Jae Kim ◽

Dong Jun Lim ◽

Mi Young Lee ◽

Woo Jin Lee ◽

Sung Eun Chang ◽

...

Keyword(s):

Atopic Dermatitis ◽

Pilot Study ◽

Severity Index ◽

Skin Lesions ◽

Treated Group ◽

Atmospheric Plasma ◽

Clinical Severity ◽

Control Treatment ◽

Cold Atmospheric Plasma ◽

Plasma Device

Abstract Introduction: Cold atmospheric plasma generates free radicals through the ionization of air at room temperature. Its effect and safety profile in patients with atopic dermatitis have not been evaluated prospectively.Objective: We aimed to investigate the effect and safety of cold atmospheric plasma in patients with atopic dermatitis with a prospective pilot study.Methods: Cold atmospheric plasma treatment or sham control treatment were applied respectively in randomly assigned and symmetric skin lesions. Three treatment sessions were performed at weeks 0, 1, and 2. Clinical severity indices were assessed at weeks 0, 1, 2, and 4 after treatment. Additionally, the microbial characteristics of the lesions before and after treatments were analyzed.Results: We included 22 patients with mild to moderate atopic dermatitis presented with symmetric lesions. We found that cold atmospheric plasma can alleviate the clinical severity of atopic dermatitis. Modified atopic dermatitis antecubital severity and eczema area and severity index score were significantly decreased in the treated group. Furthermore, scoring of atopic dermatitis score and pruritic visual analog scales significantly improved. In microbiome analysis revealed significantly reduced proportion of Staphylococcus aureus in the treated group.Conclusion: Cold atmospheric plasma can significantly improve mild and moderate atopic dermatitis without safety issues.

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Atmospheric Pressure Plasma Grafting of a Vinyl-Quaternary Compound to Nonwoven Polypropylene and Cotton

Journal of Engineered Fibers and Fabrics ◽

10.1177/155892501801300306 ◽

2018 ◽

Vol 13 (3) ◽

pp. 155892501801300

Author(s):

Carrie Cornelius ◽

Marian McCord ◽

Mohamed Bourham ◽

Peter Hauser

Keyword(s):

North Carolina ◽

Atmospheric Pressure ◽

Atmospheric Pressure Plasma ◽

Atmospheric Plasma ◽

Quaternary Compound ◽

North Carolina State University ◽

Pressure Plasma ◽

Plasma Device ◽

Plasma Grafting ◽

Graft Yield

Nonwoven polypropylene and cotton fabrics are grafted to a vinyl quaternary compound using atmospheric-pressure plasma. Two different atmospheric plasma devices are used -the NCAPS (North Carolina Atmospheric Plasma System), a dielectric barrier discharge device created by North Carolina State University, and a plasma device from APJeT® Inc. The addition of additives such as Mohr's salt, potassium persulfate, and diacrylates are assessed to see if graft yield can be increased. Acid dye tests, SEM, and XPS reveal successful grafting of the vinyl quaternary compound. A combination of all four additives is found to yield the highest graft yields and greatest uniformity.

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Enhanced Abrasion Resistance of Coated Particleboard Pre-Treated with Atmospheric Plasma

Drvna industrija ◽

10.5552/drvind.2020.1960 ◽

2020 ◽

Vol 71 (2) ◽

pp. 129-137

Author(s):

Jure Žigon ◽

Sebastian Dahle ◽

Marko Petrič ◽

Matjaž Pavlič

Keyword(s):

Cross Sections ◽

Abrasion Resistance ◽

Contact Angles ◽

Attenuated Total Reflection ◽

Atmospheric Plasma ◽

Dbd Plasma ◽

Coating Application ◽

Applied Coating ◽

Floating Electrode ◽

Lower Contact

This study aims to investigate the influence of atmospheric plasma treatment on the abrasion resistance of particleboards, as an example of a wood-based material, coated with a waterborne finish. The treatment of the substrate, prior to coating application, using a floating-electrode dielectric barrier discharge (FE-DBD) plasma, resulted in an enhanced abrasion resistance of the coated particleboards in comparison to the untreated ones during the abrasion test with a duration of 200 revolutions. This finding was related to lower contact angles of water and coating after treatment with plasma and greater hardness of the coating on the treated substrates. The micrographs of the sample cross sections recorded with scanning electron microscope showed differences in the amounts of remained coating on the abraded areas. Investigation with attenuated total reflection Fourier transform infrared spectroscopy revealed that treatment of the substrate with plasma did not affect the chemical composition nor the curing and structure of the later applied coating. Further studies should be performed to determine the resistance properties of such surface systems to other impacts.

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