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In this research, the role of B 4 C-reinforcing particles on the corrosion behaviour of Al5083/B 4 C nanocomposite has been investigated. Al/B 4 C nanocomposite powder with weight percentages of 3 and 7 of reinforcing phase was prepared by mechanical milling method. The resulting powder was initially hot-pressed and then hot-extruded. The microstructure of the sample was studied using scanning electron microscopy and their corrosion behaviour was studied using potentiodynamic polarization and scanning electrochemical impedance spectroscopy methods in different immersion time intervals. The results showed a uniform distribution of reinforcing particles and also the scattering of intermetallic particles at the surface of the samples. However, increasing the content of B 4 C particles in the composite samples enhances the cathodic and anodic reactions by increasing the content of intermetallic particles as cathodic sites on the surface, so that higher corrosion current density is observed in the composite samples with 7 wt% B 4 C. Finally, it was concluded that increasing the value of B 4 C decreases the corrosion resistance of the B 4 C-reinforced composite samples in sodium chloride solution, which makes it unsuitable in marine applications.

To increase the active surface area of copper collectors in Li-ion batteries, electrochemical deposition of porous copper films was carried out using a solution of 0.15 M CuSO 4 ·5H 2 O in 0.5 M H 2 SO 4 . Square-wave pulsating overpotential deposition was performed at overpotential amplitudes of −1100, −1250 and −1400 mV vs . Ag/AgCl on copper foil, rated for Li batteries. Energy-dispersive method analysis and a scanning electron microscope were used to characterize film morphology. X-ray diffraction method was used to analyse structural properties of the deposits. Electroactive and real surfaces of the samples were measured using cyclic voltammetry (CV) in a 0.1 M KOH solution. The results showed that by increasing the applied negative overpotential, the electroactive and real surface area of the samples were increased. As a result, the sample values of 47.13, 58.50 and 62.63 cm 2 were obtained at the respective deposition overpotential amplitudes of −1100, −1250 and −1400 mV. For untreated film, however, the value was around 9.35 cm 2 . Ultimately, it was discovered that CV is a highly effective technique for determining the real surface area of porous copper foils.

Platinum-plated niobium anodes are commonly used in the electrochemical oxidation of chlorate-containing solutions. In this research, a novel mechanism has been presented for the deactivation of Pt/Nb anodes in this process and the effect of the electrolyte temperature has been investigated in this mechanism. The samples were exposed to the accelerated life test (ALT) in the chlorate-containing electrolyte at temperatures of 35, 50, and 65 °C at a current density of 1200 mA cm −2 for 3, 10, 40, and 70 h. The electrochemical behavior of the samples was studied using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) methods at each time interval. The morphology of the samples was also observed using scanning electron microscopy (SEM), before and after the ALT. The results showed that the highest corrosion resistance is obtained in the electrolyte with a temperature of 35 °C; the temperature at which the anode has the most increased electrocatalytic activity. However, at 65 °C, the anode is deactivated after 60 h of ALT, through the dissolution of platinum coating and subsequently the substrate passivation. Generally, passivation of niobium substrate is the progressive mechanism in the electrolyte at low temperatures, while, at high temperatures, deactivation starts from platinum coating dissolution and proceeds by substrate passivation.

The Tesla valve is a non-moving check valve used in various industries to control fluid flow. It is a passive flow control device that does not require external power to operate. Due to its unique geometry, it causes more pressure drop in the reverse direction than in the forward direction. This device’s optimal performance in heat transfer applications has led to the use of Tesla valve designs in heat sinks and heat exchangers. This study investigated a Tesla valve with unconventional geometry through numerical analysis. Two geometrical parameters and inlet velocity were selected as input variables. Also, the pressure drop ratio (PDR) and temperature difference ratio (TDR) parameters were chosen as the investigated responses. By leveraging numerical data, artificial neural networks were trained to construct precise prediction models for responses. The optimal designs of the Tesla valve for different conditions were then reported using the genetic algorithm method and prediction models. The results indicated that the coefficient of determination for both prediction models was above 0.99, demonstrating high accuracy. The most optimal PDR value was 4.581, indicating that the pressure drop in the reverse flow direction is 358.1% higher than in the forward flow direction. The best TDR response value was found to be 1.862.

Vaginal infections caused by bacteria, Candida and Trichomonas vaginalis, affect millions of women annually worldwide. Symptoms and signs have limited value in differential diagnosis of three causes of vaginitis. Current laboratory methods for differential diagnosis are either expensive or time consuming. Therefore, in this work, development of a method based on gold nanoparticles has been investigated for rapid diagnosis of vaginal infections. Specific antibodies against three main causes of vaginal infections were raised in rabbits. The antibodies were then purified and conjugated to gold nanoparticles and used in an agglutination test for detection of vaginal infections. Finally, sensitivity and specificity of this test for diagnosis of vaginal infections were estimated using culture method as gold standard. Purification of antibodies from sera was confirmed by electrophoresis. Construction of nanoparticles was proved by TEM and FT-IR methods. Conjugation of antibodies to gold nanoparticles was confirmed using XPS method. Sensitivity and specificity of gold nanoparticles for diagnosis of Candida species were 100%, for Gardnerella were 100% and 93%, and for T. vaginalis was 53.3% and 100%, respectively. Gold nanoparticle-based method is a simple, rapid, accurate, and cost-effective test for differential laboratory diagnosis of vaginal infections.