scholarly journals The acceleration of water absorption time in natural silk fabrics (Bombyx Mori) irradiated with positive and negative corona plasma discharges at atmospheric pressure

2021 ◽  
Vol 1943 (1) ◽  
pp. 012023
Author(s):  
Z Muhlisin ◽  
M K Nugraha ◽  
I Rahmawati ◽  
F Arianto ◽  
N A K Umiyati ◽  
...  
Keyword(s):  
Water Absorption ◽  
Bombyx Mori ◽  
Atmospheric Pressure ◽  
Plasma Discharges ◽  
Negative Corona ◽  
Absorption Time ◽  
Natural Silk ◽  
Corona Plasma ◽  
Silk Fabrics

scholarly journals Improving water absorption time and the natural silk strength (Bombyx Mori) using atmospheric dielectric barrier discharge plasma

2021 ◽  
Vol 3 (2) ◽  
pp. 165-169
Author(s):  
Zaenul Muhlisin ◽  
Muhammad Adrian Lathif ◽  
Fajar Arianto ◽  
Pandji Triadyaksa
Keyword(s):  
Water Absorption ◽  
Discharge Plasma ◽  
Barrier Discharge ◽  
Plasma Discharge ◽  
Dielectric Barrier Discharge Plasma ◽  
Dielectric Barrier ◽  
Absorption Time ◽  
Natural Silk ◽  
Plane Electrode ◽  
Barrier Discharge Plasma

This researchaimed to obtain Dielectric Barrier Discharge plasma discharge characteristics with and without the placement of natural silkBombyx Mori on one of the electrodes. Furthermore, the strength and the water absorption time of the irradiated silk samples will be analyzed.  Plasma discharge is generated by connecting electrodes of point-to-plane configuration with a sheet of glass inserted on the plane electrode at atmospheric conditions. The characterization of plasma discharge, either with or without the natural silk samples' placement on the plane electrode, was performed by increasing A.C.'s high voltage power source to reach arch discharge. Theelectrode spacing varied from 0.7 cm to 2.5 cm with a 0.3 cm increment. Sample irradiation was performed using cold plasma for 5, 15, and 30 minutes respectively. Placing or not placing the natural silk samples on the plane electrode will increase the plasma's discharge current and increase the high voltage. Moreover, increasing the distance between the electrodes and placing the sample on the plane electrode decreases the discharge current. Using Scanning Electron Microscopy, it was found that increasing plasma irradiation time on samples decreases the silk thread'sdiameterand shortening its water absorption time. The strength of irradiated fabric was reduceduntil 15 minutes of irradiation. However, at 30 minutes of irradiation, there was an increase in sample thickness compared to control samples.

scholarly journals Effects of Anti-Graffiti Protection on Concrete Durability

2014 ◽  
Vol 634 ◽  
pp. 517-526 ◽  
Author(s):  
Elsa Neto ◽  
Ana Souto ◽  
Aires Camões ◽  
Arlindo Begonha ◽  
Paulo Cachim
Keyword(s):  
Water Absorption ◽  
Atmospheric Pressure ◽  
Surface Characteristics ◽  
Concrete Surface ◽  
Experimental Program ◽  
Concrete Durability ◽  
Protection Systems ◽  
Before And After ◽  
Paint Removal ◽  
Durability Of Concrete

The heritage of fair-faced concrete, largely built in the twentieth century and nowadays recognized as heritage to be protected, is susceptible to attacks by graffiti, a form of vandalism that causes a major social and economic impact on society. Concrete is a porous material sometimes deteriorated over the years, and the interactions between the inks and the substrate and removal methods sometimes deteriorate or alter the concrete surface, especially if it is necessary to repeat the removal process. The anti-graffiti products are applied on the surface of the concrete, hindering the adhesion of paints or preventing its penetration into the pores of concrete, which in turn facilitates their removal. However, it appears that many of the existing protective products on the market may also alter the surface characteristics of the concrete irreversibly. Considering that the durability of concrete depends on the composition and characteristics of the surface, it is essential to know the effects of anti-graffiti protection systems on the durability of concrete and adopt the appropriate methodology to preserve this heritage. Thus, an experimental program was developed for analyzing changes in durability indicators and surface properties that protect concrete from deterioration (i) concrete without protection before and after application of spray paint, (ii) concrete with protection before and after application of spray paint and (iii) after paint removal were studied. Two anti-graffiti products were evaluated: a permanent and a sacrificial one. Effects of the anti-graffiti systems on the concrete durability are investigated and the tests performed include: water absorption by capillary and immersion at atmospheric pressure. The results of the water absorption tests show that the graffiti protection reduces the water absorption into the concrete and facilitates the removal of the graffiti without affecting negatively the characteristics of the surface and thus contributing to improve its durability.

scholarly journals Generation of Porous Alumina Layers in a Polydimethylsiloxane/Hydrogen Peroxide Medium on Aluminum Substrate in Corona Discharges

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
A. Groza ◽  
A. Surmeian ◽  
C. Diplasu ◽  
C. Luculescu ◽  
C. Negrila ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Photoelectron Spectroscopy ◽  
Atmospheric Pressure ◽  
Porous Alumina ◽  
Aluminum Substrate ◽  
Corona Discharges ◽  
Negative Corona ◽  
Alumina Layer ◽  
X Ray ◽  
Anodization Process

The porous alumina (Al2O3) layer obtained at the interface between polydimethylsiloxane/hydrogen peroxide medium and aluminum substrate under charged and neutral species injection produced in negative corona discharges in air at atmospheric pressure is analyzed by different methods in this paper. The scanning electron microscopy investigations showed the uniform distribution of the pores formed in the alumina layer and their columnar structures. Both energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) measurements indicate that during the anodization process of the aluminum in the polydimethylsiloxane/hydrogen peroxide medium in corona discharge the incorporation of silicon in the structure of the alumina layer is possible.

scholarly journals DEVELOPMENT OF A COMPOSITIONAL MODIFIER FOR MODIFICATION OF WOOD BY SPECIFIED PROPERTIES

2020 ◽  
Vol 8 (1) ◽  
pp. 17-22
Author(s):  
Aleksey Aksenov ◽  
Sergey Malyukov ◽  
A. Solntsev
Keyword(s):  
Water Absorption ◽  
Dimensional Stability ◽  
Filter Paper ◽  
Atmospheric Pressure ◽  
Moisture Absorption ◽  
Friction Units ◽  
Environmental Requirements ◽  
Impregnated Wood ◽  
Modified Wood

In recent years, the production of modified wood has been actively developing abroad. This article discusses the composition of a complex modifier for modified wood, which will improve the performance of friction units with bearings made of modified wood by reducing intermolecular interactions between contacting bodies, increase dimensional stability and hardness of modified wood, and will also comply with environmental requirements. The density of the liquid components of the impregnating compositions was determined. The number of components necessary for the preparation of impregnating compositions was calculated. The impregnation technology is as follows: the impregnating composition is poured into a tin can, heated on an electric stove to 120 0C. Prepared (dried, weighed, measured on three sides and marked) samples of 15 pieces in each impregnating composition are immersed in a hot impregnating solution. Tin cans with samples are placed in a pre-heated autoclave, closed, and brought to a pressure of 40 atm. At this pressure, the samples are kept for 5 minutes. Then the pressure is brought to atmospheric pressure, the samples are removed, dried with filter paper and placed in a desiccator for cooling to a temperature of 20 ± 2 0С. After cooling, the samples are weighed on an analytical balance to the nearest 0.002 g and the three sides of the sample are measured with a caliper. The quality of impregnation of the samples was determined. Water absorption, moisture absorption, linear swelling of the samples of impregnated wood were determined.

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