Journal of Composites and Compounds
Volume:3 Issue: 8, Sep 2021

This study is aimed to fabricate the Aluminium-graphene oxide (Al-GO) composites with different concentration of GO (0.5, 1, and 2 wt. %) at 300 °C using repetitive upsetting extrusion (RUE) technique. Uniform dispersion of GO nanoplates throughout the matrix was obtained by sequence processes including the ultrasonicating, ball milling and RUE. The microstructure of composites was investigated by X-ray diffraction, scanning electron microscope and Raman analysis. The results confirmed that the Al-1GO illustrated the uniform and homogenous dispersion of GO into the Al matrix. Raman results confirm the absence of aluminum carbide phase formation during the RUE process. The mechanical properties results show the greater hardness, compressive strength and yield strength of Al-1GO than other ones. This 500% enhancement of Al-1GO in mechanical behavior may be related to desired dispersion of GO throughout the matrix. Current density of the Al matrix corrosion significantly increased from 2.65 to 15.21 (μA/cm2), when the amount of GO increased from 0 to 2 wt. % due to galvanic cor-rosion at the presence of the GO reinforcement. ©2021 JCC Research Group.

Turbidimeters are low-cost devices, which are widely used for suspended sediment monitoring (SSM). The spe-cific turbidity is typically relative to 1/d (d is the diameter of particles) regarding the suspensions with mono-sized sphere-shaped particles. As the production of the dispersed suspension of TiO2-NPs is vital for their photocatal-ysis applications, turbidity provides a test to measure the dispersion of TiO2-NPs. In the present paper, the per-formance of a self-manufactured turbidimeter device has been investigated using the suspensions of TiO2-NPs in different alcoholic media. The results showed that over time, the intensity of light passing through the upper part of the test tube containing TiO2-NPs suspension increased, suggesting the settlement of TiO2 nanoparticles. In the middle part of the test tube; however, an almost stable trend was observed, which was more evident in the case of isopropanol with higher viscosity. The results also illustrated that there was no relation between the concentration of suspension and the value of transmitted light for concentration below 0.08 g/l; however, for concentrations above that, the intensity of transmitted light decreased with the increase of suspension concentration. ©2021 JCC Research Group

The search for sustainable materials has grown globally due to the struggle against environmental impacts. From the recycling of PET packaging and the use of steel mill slag residue, from the steel production, it was developed in this work composites of PET matrix with additions of geopolymer obtained from steel mill slag. The compos-ites were produced with concentrations of 0, 20, 40, and 60% of geopolymer and were characterized by XRD, FTIR, TGA, DSC, and SEM. The XRD analyses indicated the presence of mineral constituents referring to the geopolymer in the composites. Through the thermal analyses, it was observed that the addition of geopolymer promoted the increase in thermal stability, besides increasing the crystallinity in concentrations of 40 and 60% of geopolymer. From the micrographs, it was observed that the addition of reinforcement changed the morphology of the material, promoting an increase in the porosity of the material. From the characterizations, it is possible to state that the addition of geopolymers in the PET matrix produces low-cost composites with good properties and can be used in engineering applications. ©2021 JCC Research Group.

In this paper, the leaching of a sulfide concentrate, from “Sarcheshmeh Copper Complex”, by sulfuric acid is studied. The influences of sulfuric acid concentration and leaching temperature were scrutinized to optimize the processing parameters and to disclose the kinetics of the extraction process. The leaching rate of copper was not significantly improved with enhancing the temperature and concentration of sulfuric acid. The formation of elemental sulfur was found as a reducer of the leaching rate. Only ~70% of copper was extracted by adding 1M ferric sulfate as the oxidant agent, as well as increasing the leaching temperature up to 85 °C. By leaching the mechanically activated concentrate in Fe2(SO4)3-doped H2SO4 at 85 °C, the amount of extracted copper was ~90% after 180 min. The experimental results were excellently fitted with the diffusion-controlled kinetic model as the activation energy of ~27 kJ/mol was estimated. ©2021 JCC Research Group

The aim of this paper is to investigate the free vibration of functional-graded (FG) cylindrical helical springs. Model differential equations of homogeneous helical springs are extended to the vibration of FG helical springs. The equations are discretized using finite difference method for space. The time dependent equations are solved using a GMRES method. The initial axial and rotational displacements are applied at the free end of the spring manually and then released. The validated numerical model is then adopted to establish the effects of the FG material index on the model natural frequencies obtained by FFT analysis. According to the results, in both ho-mogeneous and FG helical springs, the amplitudes of axial and rotational displacements increase as they approach the free end of the spring. The numerical results indicate that the FG material index strongly affects the dynamic behavior of the cylindrical helical springs. The amplitudes of the oscillations are damped efficiently and by in-creasing the material gradient index. ©2021 JCC Research Group.

Zinc oxide (ZnO) is used for various purposes because of its special physico-chemical properties, including large band gap, high binding energy of exciton, nontoxicity, high chemical and thermal stability, large piezoelectric constants, and wurtzite crystal structure with various and widespread applications in electronics, optoelectronics, biochemical sensing, biomedical, and energy-saving systems. This review mainly aimed to present the recent improvement in ZnO-based composite materials with utilization in energy storage systems with a specific focus on lithium-ion batteries, dye-sensitized solar cells, and supercapacitors. The first part of this paper looks at the structure and properties of ZnO and then describes some of the most common synthesizing methods of ZnO com-posites, including electrochemical, chemical, solvo/hydrothermal, and physical deposition methods. Finally, the recent advancement of ZnO-based composite materials applied in energy storage systems was discussed. ©2021 JCC Research Group

Tissue engineering (TE) employs biological, chemical, and engineering methods to regenerate and restore injured or lost living tissues by applying biologically activated biomaterials, cells, and molecules. The fast and convenient restoration of tissue is a great challenge, emphasizing the need to imitate tissue structure and its physicochemical, biological, and mechanical behavior to give back the desired functionality of damaged tissue. Depending on the particular tissue, numerous requirements have to be fulfilled with the help of material and scaffold design that provides a base for cell adhesion and proliferation. As a result, countless biodegradable and bioresorbable materials have been extensively examined. Composite systems combine the benefits of bioactive ceramics and polymers, which seem to be good alternatives for bone tissue engineering. This article intends to introduce bioac-tive polymer, tissue engineering methods, the kinds of biomaterials applied in scaffold invention, and the different approaches to producing the bioactive polymer-based composites with various structures such as porous, mem-brane, and 3D structure. Biomaterials and invention techniques could crucially influence the consequences of the scaffold's design architectures, cell proliferation, and mechanical behavior. Moreover, an excellent scaffold assists cell generation and the provision of cell nutrients in the human body with their particular material characteristics. ©2021 JCC Research Group.