Characterization and Corrosion Properties of Fluoride Conversion Coating Prepared on AZ31 Magnesium Alloy

Wrought AZ31 magnesium alloy was used as the experimental material for fluoride conversion coating preparation in Na[BF4] molten salt. Two coating temperatures, 430 °C and 450 °C, and three coating times, 0.5, 2, and 8 h, were used for the coating preparation. A scanning electron microscope and energy-dispersive X-ray spectroscopy were used for an investigation of the surface morphology and the cross-sections of the prepared coatings including chemical composition determination. The corrosion resistance of the prepared specimens was investigated in terms of the potentiodynamic tests, electrochemical impedance spectroscopy and immersion tests in the environment of simulated body fluids at 37 ± 2 °C. The increase in the coating temperature and coating time resulted in higher coatings thicknesses and better corrosion resistance. Higher coating temperature was accompanied by smaller defects uniformly distributed on the coating surface. The defects were most probably created due to the reaction of the AlxMny intermetallic phase with Na[BF4] molten salt and/or with the product of its decomposition, BF3 compound, resulting in the creation of soluble Na3[AlF6] and AlF3 compounds, which were removed from the coating during the removal of the secondary Na[MgF3] layer. The negative influence of the AlxMny intermetallic phase was correlated to the particle size and thus the size of created defects.

Stabilitas Daging Ayam dengan Pelapisan Edible Coating Berbahan Kasein-Kitosan Selama Penyimpanan

The purpose of this study were to determine the effect of the stability of the use of casein edible coatings and chitosan on chicken meat with different storage times in terms of peroxide numbers, iodine numbers, antioxidant activity, bacterial counts, S. aureus, E. coli, and Salmonella sp. The treatment of chicken meat coated with edible coating temperature of ± 8 oC with a difference of shelf life for 1 day, 4 days, 10 days, 12 days, 14 days and 21 days. Research data will be analyzed using Analysis of Variance and followed by Duncan's Multiple Range Test (UJBD) if there are significant differences. The results showed that chicken meat coated with casein chitosan edible coating with long storage treatment gave a very significant effect (P <0.01) on the value of iodine numbers, peroxide numbers, and antioxidant activity, ALT and S. aureus. Casein and chitosan edible coating can provide stability in a certain shelf life at a temperature of 8 oC.

Development of Polydopamine Forward Osmosis Membranes with Low Reverse Salt Flux

Application of forward osmosis (FO) is limited due to membrane fouling and, most importantly, high reverse salt fluxes that deteriorate the concentrated product. Polydopamine (PDA) is a widely used, easily applicable, hydrophilic, adhesive antifouling coating. Among the coating parameters, surprisingly, the effect of PDA coating temperature on the membrane properties has not been well studied. Polyethersulfone (PES) 30 kDa ultrafiltration membranes were PDA-coated with varying dopamine concentrations (0.5–3 g/L) and coating temperatures (4–55 °C). The quality of the applied coating has been determined by surface properties, water permeability and reverse salt flux using a 1.2 M MgSO4 draw solution. The coating thickness increased both with the dopamine concentration and coating temperature, the latter having a remarkably stronger effect resulting in a higher PDA deposition speed and smaller PDA aggregates. In dead-end stirred cell, the membranes coated at 55 °C with 2.0 g/L dopamine showed NaCl and MgSO4 retentions of 41% and 93%, respectively. In crossflow FO, a low reverse MgSO4 flux (0.34 g/m2·h) was found making a very low specific reverse salt flux (Js/Jw) of 0.08 g/L, which outperformed the commercial CTA FO membranes, showing the strong benefit of high temperature PDA-coated PES membranes to assure high quality products.

Highly qualified InP based QDs through a temperature controlled ZnSe shell coating process and their DFT calculations

In the InP/ZnSe core/shell QD formation, the higher shell coating temperature resulted in regular tetrahedron shape and narrow emission FWHM.

Carbon nano-fiber forest foundation for ruthenium oxide pseudo-electrochemical capacitors

Effect of ruthenium oxide coating temperature on directly grown carbon nanofibers for supercapacitor application is studied.

Importance of Blade-Coating Temperature for Diketopyrrolopyrrole-based Thin-Film Transistors

In this work, the effect of blade-coating temperature on the electrical properties of a conjugated donor–acceptor copolymer containing diketopyrrolopyrrole (DPP)-based thin-film transistors (TFTs) was systematically analyzed. The organic semiconductor (OSC) layers were blade-coated at various blade-coating temperatures from room temperature (RT) to 80 °C. No remarkable changes were observed in the thickness, surface morphology, and roughness of the OSC films as the blade-coating temperature increased. DPP-based TFTs exhibited two noticeable tendencies in the magnitude of field-effect mobility with increasing blade-coating temperatures. As the temperature increased up to 40 °C, the field-effect mobility increased to 148% compared to the RT values. On the contrary, when the temperature was raised to 80 °C, the field-effect mobility significantly reduced to 20.9% of the mobility at 40 °C. These phenomena can be explained by changes in the crystallinity of DPP-based films. Therefore, the appropriate setting of the blade-coating temperature is essential in obtaining superior electrical characteristics for TFTs. A blade-coating temperature of 40 °C was found to be the optimum condition in terms of electrical performance for DPP-based TFTs.