النشر العلمي

  • Synergistic Effect of Atmospheric Pressure Plasma Pre-Treatment on Alkaline Etching of Polyethylene Terephthalate Fabrics and Films

Dyeing of PET materials by traditional methods presents several problems. Plasma technology has received enormous attention as a solution for the environmental problems related with textile surface modifications, and there has been a rapid development and commercialization of plasma technology over the past decade. In this work, the synergistic effect of atmospheric pressure plasma on alkaline etching and deep coloring of dyeing properties on polyethylene terephthalate (PET) fabrics and films was investigated. The topographical changes of the PET surface were investigated by atomic force microscopy (AFM) images, which revealed a smooth surface morphology of the untreated sample whereas a high surface roughness for the plasma and/or alkaline treated samples. The effects of atmospheric pressure plasma on alkaline etching of the structure and properties of PET were investigated by means of differential scanning calorimetry (DSC), the main objective of performing DSC was to investigate the effect of the plasma pre-treatment on the Tg and Tm. Using a tensile strength tester YG065H and following a standard procedure the maximum force and elongation at maximum force of PET materials was investigated. Oxygen and argon plasma pre-treatment was found to increase the PET fabric weight loss rate. The color strength of PET fabrics was increased by various plasma pre-treatment times. The penetration of plasma and alkaline reactive species deep into the PET structure results in better dyeability and leaves a significant effect on the K/S values of the plasma pre-treated PET. It indicated that plasma pre-treatment has a great synergistic effect with the alkaline treatment of PET.

published in Plasma Science and Technology

  • Improving the low temperature dyeability of polyethylene terephthalate fabric with dispersive dyes by atmospheric pressure plasma discharge

Polyethylene terephthalate (PET) fiber and textile is one of the largest synthetic polymer commodity in the world. The great energy consumption and pollution caused by the high temperature and pressure dyeing of PET fibers and fabrics with disperse dyes has been caused concern these years. In this study, an atmospheric pressure plasma with fine and uniform filament discharge operated at 20 kHz has been used to improve the low temperature dyeability of PET fabric at 95◦C with three cation disperse dyes: Red 73, Blue 183 and Yellow 211. The dyes uptake percentage of the treated PET fabrics was observed to increase as twice as much of untreated fabric. The color strength rate was increased more than 20%. The reducing of the water contact angle and the raising of the capillary height of treated PET fabric strip indicate its hydrophilicity improvement. Scanning electron microscope (SEM) results display nano to micro size of etching pits appeared uniformly on the fiber surface of the treated PET. Simultaneously, Xray photoelectron spectroscopy (XPS) analysis indicates an increase of the oxygen content in the surface

published in Applied Surface Science

  • Interfacial complexation behavior of anionic and cationic cellulose derivatives

The oppositely charged cellulose derivatives, quaternized cellulose (QC) and carboxymethyl cellulose
(CMC), were alternately deposited on silicon or quartz substrates by interfacial complexation, i.e. layerby-layer (LbL) assembly, to prepare thin films. The effects of pH value, ionic strength and temperature on
thin-film growth and morphology were investigated. The main chains of QC and CMC, composed of
glucose rings, are hydrophilic and rigid, and hence QC and CMC show a different assembly behavior
compared with synthetic vinyl polyelectrolytes such as polystyrene sulfonate and poly(diallyldimethylammonium). As the pH value increases, in the region from pH 3 to pH 5, QC and CMC can be LbLassembled to prepare thin films; in the neutral pH region, it is very difficult to assemble QC and CMC;
and when the pH value is higher than 10, QC and CMC can again be deposited to fabricate thin films.
The LbL assembly of QC and CMC is sensitive to ionic strength. On adding 0.1 M NaCl into the
assembling solution, the thin-film growth decreases enormously. Increasing the temperature accelerates
the growth in thickness of the films.
 

published in RSC Advances

  • Sulieman M. S. Zobly, “New orthogonal Matching Pursuit Algorithm for 2D different Dimension Sparse Signal Reconstruction

The recovery algorithm is the backbone of compressed sensing (CS). Most of the algorithms were designed for 1D signal reconstruction and a few were designed for 2D signals. To reconstruct 2D signals, in most cases signals were converted into 1D signal. In some application signals and images with 2D different dimension (N-by-M) can’t be recovered with existing 1D or 2D recovery algorithms, thus in this work we proposed a new recovery algorithm known as 2D Different Dimension Orthogonal Matching Pursuit (OMP) Algorithm, so as to solve the problem of 2D Different Dimension Sparse Signals and images, which is represented an accomplishment of 2D OMP. In the 2D different dimension OMP the observation/measurement is processed as a matrix instead of vectors in the other CS algorithms. Comparing the proposed algorithm with current algorithms, the proposed algorithm reconstructs the 2D different dimension sparse signal faster than the other algorithms, and can be implemented easier.

published in International Conference on Computing, Control, Networking, Electronics and Embedded Systems Engineering, IEEE,

  • Influence of Operational Parameters on Layer-by-layer Assembled Cellulose Derivatives Thin Film

Abstract. Positively charged cellulose derivative quaternized cellulose (QC), was layer-by-layer
(LbL) assembled with negatively charged cellulose derivative carboxymethyl cellulose (CMC) to
produce the thin film. The factors of dipping and rinsing time on the thin film growth were
investigated. FT-IR confirmed that QC and CMC can be layer by layer assembled in different
dipping and rinsing time. As dipping time increases, the thickness of fabricated QC/CMC thin film
will increase, while increasing rinsing time leads to decrease in the thickness of the QC/CMC thin
film.
 

published in Atlantis Press

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