Engineering and Technology Journal

Graphene nanofilms were deposited by the spray coating method at different concentrations (0.05, 0.1, 0.2, 0.3, 0.4, and 0.5 g) and prepared at 120°C. The prepared nanofilms were characterized in terms of their structural, morphological, optical, and electrical properties. The results confirm the formation of high-purity and high-crystallinity graphene nanofilms with a layered nanosheet morphology. The X-ray diffraction pattern shows the presence of pure graphene with (002) crystal planes. SEM Images show that the intended graphene films are symmetrical with few wrinkles on their surface. The graphene films show semi-transparent behavior with a maximum transmission of 50%. Raman spectroscopy shows that the relative intensity, position, and shape of the G and 2D Raman peaks change with the number of graphene layers. The electrical conductivity increases with temperature, and the conductivity can be further increased depending on the metal or metal oxide functionalization. The electrical conductivity of the graphene film deposited at a concentration of 0.3 g was significantly higher than the values reported for other concentrations. The results of this study suggest that the physical and electrical properties of spray-coated graphene films can be optimized by controlling the solution concentration, which could have potential applications in transparent conductive films.

Image encryption is a crucial area for researchers in information security, which protects digital images from unauthorized access. This paper proposes a novel image encryption scheme based on the multi-chaotic system. This paper is about encrypting color images based on a 2D Henon map and a 3D Lorenz map. We used the 2D Henon map equation to generate a new S-Box, thus creating a solid cipher that is difficult to break (for the confusion operation). We then generate keys from the 3D Lorenz map for the shifting process (for diffusion operation). A comparative analysis and the simulation test show that the suggested image cryptosystem has some excellent properties, including high sensitivity, fast encryption/decryption, a large keys-pace, excellent statistical properties related to the ciphertext, etc.

Solid polymeric electrolytes have become crucial today due to their stability and high conductivity. Recently, lithium ion-doped polymeric electrolytes have gained intense attention for their superior ability to create highly conductive electrolytes for batteries and energy storage. This innovative electrolyte type has displaced many traditional systems due to their flammability and bulkiness. Traditional liquid organic electrolytes pose risks due to their flammable and unstable nature. Solid-state composite electrolytes offer both mechanical stability and electrical conductivity by using solid polymeric matrices like polyethylene oxide and polyurethane reinforced with inert fillers like alumina and titanium dioxide. Polyethylene oxide (PEO)-based materials show promise as polymer hosts for high-energy-density lithium batteries due to their safety, cost-effectiveness, and compatibility with lithium salt. However, the linear PEO's insufficient ionic conductivity, stemming from high crystallinity in ethylene oxide chains, limits production at low temperatures. This review delves into lithium salt effects, matrix types, plasticizer and filler impact, and composite electrolyte mechanisms

Using the sol-gel technique, this study successfully synthesized two types of nanoparticles, ZnO and TiO2. The Fourier-transform infrared (FTIR) spectrum exhibited a broad peak, providing insights into crucial chemical bonds. The average grain sizes, 18.6 nm for ZnO and 12.6 nm for TiO2 were determined through X-ray diffraction (XRD). Scanning electron microscopy (SEM) images of the (ZnO & TiO2) powder revealed the presence of pores and agglomeration. The antimicrobial efficacy of these nanoparticles was evaluated against Gram-negative bacteria (E. coli and Proteus) and Gram-positive bacteria (Staph. aureus). The results demonstrated the capability of both ZnO and TiO2 to impact bacterial survival rates, with ZnO nanoparticles exhibiting a superior effect compared to TiO2 nanoparticles. This research contributes valuable insights into the antimicrobial properties of ZnO and TiO2 nanoparticles, emphasizing their potential applications in combating bacterial infections.