arXiv subjects

Erfan Salahinejad

Publications and source records attributed to Erfan Salahinejad.

10 recordsLinked to original sources

arXiv2026

Effects of compocasting process parameters on microstructural characteristics and tensile properties of A356-SiCp composites

The effects of compocasting process parameters on some structural and tensile characteristics of the A356-10% SiCp (volume fraction) composites were studied. Semisolid stirring was carried out at temperatures of 590, 600 and 610 C with stirring speeds of 200, 400 and 600 r/min for 10, 20 and 30 min. The distribution of the SiC particles within the matrix, porosity content and tensile properties of the obtained samples were examined. The structural evaluations show that by increasing the stirring time and decreasing the stirring temperature, the uniformity in the particle distribution is improved; however, by increasing the stirring speed the homogeneity firstly increases and then declines. It is also found that by increasing all of the processing parameters, the porosity content is enhanced. From the tensile characteristics viewpoint, the optimum values of the speed, temperature and time are found to be 400 r/min, 590 C and 30 min, respectively. The contribution of the reinforcement distribution uniformity prevails over that of the porosity level to the tensile properties.

cond-mat.mtrl-sci↗

arXiv2026

Efficacy of 3D-Printed chitosan-cerium oxide dressings coated with vancomycin-loaded alginate for chronic wounds management

Multifunctional wound dressings with antibacterial and antioxidant properties hold significant promise for treating chronic wounds; however, achieving a balance of these characteristics while maintaining biocompatibility is challenging. To enhance this balance, this study focuses on the design and development of 3D-printed chitosan-matrix composite scaffolds, which are incorporated with varying amounts of cerium oxide nanoparticles (0, 1, 3, 5, and 7 wt%) and subsequently coated with a vancomycin-loaded alginate layer. The structure, antibiotic drug delivery kinetics, biodegradation, swelling, biocompatibility, antibacterial, antioxidant, and cell migration behaviors of the fabricated dressings were evaluated in-vitro. The findings reveal that all of the formulations demonstrated a robust antibacterial effect against S. aureus bacterial strains in disk diffusion tests. Furthermore, the dressings containing cerium oxide nanoparticles exhibited proper antioxidant capabilities, with over 78.1% reactive oxygen species (ROS) scavenging efficiency achieved with 7% cerium oxide nanoparticles. The sample containing 5% cerium oxide nanoparticles was identified as the optimal formulation, characterized by the most favorable cell biocompatibility, an ROS scavenging ability of over 73.4%, and the potential to close the wound bed within 24 h. This study highlights that these dressings are promising for managing chronic wounds by preventing infection and oxidative stress in a correct therapeutic sequence.

physics.app-ph↗

arXiv2026

Chitosan/alginate bionanocomposites adorned with mesoporous silica nanoparticles for bone tissue engineering

The regeneration of oral and craniofacial bone defects ranging from minor periodontal and peri-implant defects to large and critical lesions imposes a substantial global health burden. Conventional therapies are associated with several limitations, highlighting the development of a unique treatment strategy, such as tissue engineering. A well-designed scaffold for bone tissue engineering should possess biocompatibility, biodegradability, mechanical strength, and osteoconductivity. For this purpose, mesoporous silica nanoparticles (MSNs) were synthesized and incorporated at different ratios (10, 20, and 30%) into alginate/chitosan (Alg/Chit)-based porous composite scaffolds fabricated through the freeze-drying method. The MSN incorporation significantly improved the mechanical strength of the scaffolds while showing a negligible decreasing effect on the porosity. All of the samples showed desirable swelling behaviors, which is beneficial for cell attachment and proliferation. The MSN-containing scaffolds indicated a decreased hydrolytic degradation in an MSN percentage-dependent manner. The fabricated scaffolds did not depict cytotoxic characteristics. The Alg/Chit/MSN30 scaffolds not only showed noncytotoxic properties, but also increased the cell viability significantly compared to the control group. The biomineralization properties of the MSN-containing nanocomposite scaffolds were significantly higher than the Alg/Chit composite, suggesting the potential of these nanoparticles for bone tissue engineering applications. Taken together, it is concluded that the Alg/Chit/ MSN30 scaffolds are considerable substances for bone tissue regeneration, and MSN has a great tissue engineering potential in addition to its extensive biomedical applications.

physics.med-ph↗

arXiv2026

The effect of graphene orientation on permeability and corrosion initiation under composite coatings

The unique anisotropic properties of graphene, particularly impermeability, have made it a promising candidate for further advances in corrosion prevention applications. Despite the large number of experimental works divulging the use of graphene in anticorrosion coatings, there is no report on the numerical modelling and simulation of the relationships between the orientation of graphene sheets in composite coatings and the introduced corrosion protection efficiency, to our knowledge. Herein, it is tried to model the influence of the orientation of graphene sheets dispersed in organic coatings on the diffusivity and flux of corrosive substances besides the corrosion initiation time of the protected substrates. To discover the relationship between the graphene orientation and corrosion-related phenomena, this study introduces a novel model consisting of a trigonometric factor named unprotected projected surface area proportion, which calculates corrosion-related parameters based on the principal Fick's laws. The model reveals that the decrease in the angle between graphene sheets and the substrate is highly beneficial for postponing the corrosion onset. It is accordingly estimated that a mismatch angle of 10 degree can slow down the diffusion process significantly and delay the corrosion initiation by around 65 times in a 100 micron thick epoxy/graphene composite coating in comparison to the counterpart with the perpendicular alignment. The predicted corrosion parameters were in a good agreement with the experimental data, indicating the merit of the proposed model. Thus, this model can be further employed as the fundamental of future research on the optimum graphene orientation in anticorrosion composite coatings.

physics.app-ph↗

arXiv2026

Advances in ion-doping of Ca-Mg silicate bioceramics for bone tissue engineering

The use of bioceramics as hard tissue substitutes is extensive due to their excellent biocompatible and osteogenic behaviors. Among various bioceramics, Ca-Mg silicates are unique from the viewpoints of osteoinductive and mechanical properties, as well as their outstanding osteoconductive and angiogenic behaviors owing to the release of Si, Ca and Mg. Despite these distinct advantages, different compositions of these bioceramics still require mechanical and biological enhancements for further applications. For this purpose, doping with some ions like F-, Sr2+, Cu2+, Eu2+, Ba+, Ce3+ and some alkali cations has been proved to be a valued approach. This review attempts to bring together areas for the performance improvement of the further researched Ca-Mg silicates (i.e., diopside, akermanite, bredigite and monticellite) and the alteration of these compositions via ion-doping. It is concluded that a correct choice of dopants incorporated at the optimal concentration makes these silicates ideal bone substitutes competing or even superior to calcium phosphates (apatites) and bioglasses which are known as the most prominent bioceramics.

physics.chem-ph↗

arXiv2026

A combined criterion of surface free energy and roughness to predict the wettability of non-ideal low-energy surfaces

The significance of wettability between solid and liquid substances in different fields encourages scientists to develop accurate models to estimate the resultant apparent contact angles. Surface free energy (SFE), which is principally defined for ideal (flat) surfaces, is not applicable to predict the wettability of real (rough) surfaces. This paper introduces a new parameter, namely normalized surface free energy (NSFE) as a combination of SFE and roughness, to predict the contact angle of liquids on non-ideal low-energy surfaces. The remarkable consistency of the predicted and measured contact angles of liquids on some rough surfaces also confirm the validity of the approach.

physics.chem-ph↗

arXiv2026

Co-doping of silicate bioceramics as a potential strategy to further enhance mono-doping consequences

Silicate bioceramics have attracted significant attention in medical applications, particularly in hard tissue regeneration, because of their controllable chemical, physical, and biological functionalities, while ensuring biocompatibility. The coordination of silicate bioceramics with mono-dopants has been extensively studied to enhance their osteogenesis, angiogenesis, and antibacterial activity. However, the concept of employing dual or multiple co-doping to further enhance these biomaterials still demands more attention. This review paper originally focuses on the effect of chemical interactions among co-dopants and the principal constituents of the silicates, on the bio-behavior of these bioceramics. Additionally, future prospects of co-doped silicate bioceramics are outlined, including in vivo studies, clinical trials, and potential commercialization.

physics.chem-ph↗

arXiv2025

Influence of Pt/Ru ratios on the oxidation mechanism of MCrAlYTa coatings modified with Pt-Ru overlays

This study investigates the influence of varying Pt/Ru ratios on the oxidation mechanism of NiCoCrAlYTa coatings with electrodeposited, vacuum-annealed Ptsingle bondRu overlays. Weight change measurements, scanning electron microscopy/energy dispersive X-ray spectrometry (SEM/EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) were used for high-temperature oxidation analyses, showing superior resistance with higher Pt contents. This was attributed to the creation of a denser, thinner, and more homogeneous layer of alumina (alpha-Al2O3) in the thermally-grown oxide (TGO) layer. On the contrary, an increase in Ru contents led to the development of other oxides and microcracks along with alumina in the TGO layer, undermining oxidation protection. The accommodation of Ti and Ta, in the minimally-deteriorative form of carbide, along with Y into the TGO layer with increasing Pt contents further enhanced oxidation resistance. In addition to the explored significant impact of the Pt/Ru ratio on oxide scale characteristics and oxidation resistance, the lower cost of Ru compared to Pt suggests the potential for designing cost-effective systems through optimized Pt/Ru ratios and microstructural engineering.

cond-mat.mtrl-sci↗

arXiv2025

Enhanced Vascularity in Gelatin Scaffolds via Copper-Doped Magnesium-Calcium Silicates Incorporation: In-Vitro and Ex-Ovo Insights

Addressing a critical challenge in current tissue-engineering practices, this study aims to enhance vascularization in 3D porous scaffolds by incorporating bioceramics laden with pro-angiogenic ions. Specifically, freeze-dried gelatin-based scaffolds were infused with sol-gel-derived powders of Cu-doped akermanite (Ca2MgSi2O7) and bredigite (Ca7MgSi4O16) at various concentrations (10, 20, and 30 wt%). The scaffolds were initially characterized for their structural integrity, biodegradability, swelling behavior, impact on physiological pH, and cytocompatibility with human umbilical vein endothelial cells (HUVECs). The silicate incorporation effectiveness in promoting vascularity was then assessed through HUVEC attachment, capillary tube formation, and ex-ovo chick embryo chorioallantoic membrane assays. The findings revealed significant improvements in both in-vitro and ex-ovo vascularity of the gelatin scaffolds upon the addition of Cu-doped akermanite. The most effective concentrations were determined to be 10 and 20%, which led to notable HUVEC metabolic activity, a well-spread morphology with extensive peripheral filopodia and lamellipodia at 10% and a cobblestone phenotype indicative of in-vivo endothelium at 20% during cell attachment, the formation of complex networks of tubular structures, and robust vascularization in chick embryo development. Moving forward, the incorporation of Cu-doped akermanite into tissue-engineering scaffolds shows great potential for addressing the limitations of vascularization, especially for critical-sized bone defects, by facilitating the controlled release of pro-angiogenic and pro-osteogenic ions.

physics.med-ph↗

arXiv2025

Comparative analysis of electrodeposited Pt, Ru and Pt-Ru overlays for high-temperature oxidation protection

Platinum (Pt) and ruthenium (Ru), both members of the platinum-group metals (PGMs), are renowned for their exceptional resistance to corrosion, oxidation, and high temperatures, making them promising candidates for advanced high-temperature applications. This study investigates the direct current (DC) electrodeposition of Pt, Ru, and a binary Pt-Ru alloy onto NiCoCrAlYTa-coated single-crystal superalloy CMSX-4, along with their vacuum annealing and respective effects on the isothermal oxidation behavior of the system at 1100 °C. All the electrodeposited overlays demonstrated substantial enhancement in oxidation resistance. However, Pt exhibited the highest protection efficiency, Ru the least, and the Pt-Ru alloy provided an intermediate level of performance. Microscopic and X-ray diffraction analyses revealed that the competitive formation of protective α-Al2O3 and spinel NiAl2O4 phases on the coated surfaces played a crucial role in determining the oxidation resistance, driven by atomic interactions between the elements in the NiCoCrAlYTa bond coat and the overlay metals. Despite Ru's relatively lower oxidation resistance compared to Pt, its significantly lower cost offers potential advantages in cost-sensitive, high-temperature applications. These findings provide valuable insights into optimizing Pt-group metal coatings for durability in high-performance systems.

cond-mat.mtrl-sci↗