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In recent years, the processes used in wastewater treatment have received significant advances in various fields, including the electrochemical coagulation process as a significant innovation in the water and wastewater industry. The application of electrochemical technologies in the water and wastewater industry is very diverse. This technique has been applied in various situations and industries to remove a wide range of pollutants. Reactive dyes are a group of dyes widely used for dyeing cellulose fibers, especially linen fabrics used. The anthracavon dyes after the azo dyes are the second group of textile dyes. Reactive blue 19 is the anthraquinone dye in terms of color factor. Various methods have been used to treat this type of wastewater, including various physical and chemical treatment methods (such as filtration, settling, ozonation), each with its own disadvantages such as: low efficiency, high cost, high time and cause secondary pollution. Accordingly, electrochemical coagulation treatment to remove contamination from dye wastewater due to its high efficiency is studied. The purpose of this study was to evaluate the electrochemical removal of reactive blue 19 dye using iron and aluminum electrodes. The dye concentration was also considered at 200 mg/L for all stages and all experiments were performed at ambient temperature. Main parameters such as electrode spacing, type of electrode arrangement, anode electrode (iron and aluminum), coating of aluminum electrode with ZnO nanoparticles by physical evaporation layer-addressing method and evaluation of coating performance by scanning speed cyclic voltammetry system and different voltage ranges were used. In the optimum condition in the removal of synthetic contaminants including electrode distance of 3 cm, parallel monopolar electrode arrangement, use of iron anode electrode pair and aluminum cathode with ZnO nanoparticle coating, retention time equals to 32.66 minutes, current density 14.34 mA/cm2 and initial pH of 4, the percentage of dye wastwater was 93.8 percent. The use of zinc oxide nanoparticles coated by the physical evaporation layering method also improved the 173.12% electrical current.

The structural and optical properties of polycrystalline silicon films obtained on a silicon wafer by electron beam physical vapor deposition (EBPVD), were studied in this paper. These films were initially amorphous and changed to a crystalline solid phase during annealing. Annealing was performed in an inert gas atmosphere tube furnace at different temperatures. Micro-structure of the films was analyzed to know the relationship between the crystalline / amorphous composition, grain size and characteristics of the films. The results showed a decrease in roughness with increasing annealing temperature and structural density. Moreover, results of Micro-Raman spectrum showed formation and increase of silicon nanocrystals in the annealed condition when the thickness of the coating increased due to structural defects. [ABSTRACT FROM AUTHOR]

Wear is one of the most detrimental mechanisms which can affect the performance of many industrial systems. TiN coating due to its unique properties such as resistance to wear, oxidation, and heat is widely used in mechanical elements. In this research, TiN coating has been coated on steel substrate using a physical vapor deposition method. The coating’s properties have been obtained using nano-indentation test. Pin on disk wear test has been conducted while the disks are coated. The tests are conducted under three different loads and different speeds. It was shown that the samples with thicker coating show a better tribological performance. In this study, the relationship between wear and entropy has been investigated in order to predict the wear rate for different materials by predicting temperature. Also, temperature changes over time were predicted in two states of with and without coating. It was also shown that the samples with thicker coating have better wear resistance. One of the innovations of this research is the ability to establishing a correlation between the wear rate and produced temperature. [ABSTRACT FROM AUTHOR]

Nitride coatings with excellent hardness and wear resistance have been deposited by physical vapor deposition (PVD) in recent years. For most applications, the load bearing and adhesion of coatings are very important and can determine the life and performance of the final components. In this study, CrN/CrAlN nanostructured coatings with different thicknesses and numberes of layers were deposited on the stainless steel AISI 420 and hot-work tool steel by cathodic arc evaporation. Nanoindentation, X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS) were used for the structural characterization and estimation of stress in the coatings. Adhesion of coatings was evaluated by scratch adhesion and VDI 3198 Rockwell tests. The results revealed the high values of compressive residual stress in the physical vapor deposited coatings, in the range of 500 to 1800 MPa, with a detrimental effect on coating adhesion. Load bearing capacity was observed to be dependent on the thickness and adhesion of coating, reaching the maximum at an optimum thickness. Overall, the results proved that the type of steel substrate could have a significant influence on the coating adhesion. [ABSTRACT FROM AUTHOR]

This paper reviews briefly the development of physical vapour deposition based HTS thin film preparation technologies to today’s state-of-the-art methods. It covers the main trends of in-situ process and growth control. The current activities to fabricate tapes for power applications as well as to tailor interfaces in cuprate are described. Some future trends in HTS thin film research, both for science as well as application driven activities are outlined.