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Purpose The lattice Boltzmann simulation of fluid flow in partial porous geometries with curved porous-fluid interfaces has not been investigated yet. It is mainly because of the lack of a method in the lattice Boltzmann framework to model the hydrodynamic compatibility conditions at curved porous-fluid interfaces, which is required for the two-domain approach. Therefore, the purpose of this study is to develop such a method. Design/methodology/approach This research extends the non-equilibrium extrapolation lattice Boltzmann method for satisfying no-slip conditions at curved solid boundaries, to model hydrodynamic compatibility conditions at curved porous-fluid interfaces. Findings The proposed method is tested against the results available from conventional numerical methods via the problem of fluid flow through and around a porous circular cylinder in crossflow. As such, streamlines, geometrical characteristics of recirculating wakes and drag coefficient are validated for different Reynolds (5 ≤ Re ≤ 40) and Darcy (10−5 ≤ Da ≤ 5 × 10−1) numbers. It is also shown that without applying any compatibility conditions at the interface, the predicted flow structure is not satisfactory, even for a very fine mesh. This result highlights the importance of the two-domain approach for lattice Boltzmann simulation of the fluid flow in partial porous geometries with curved porous-fluid interfaces. Originality/value No research is found in the literature for applying the hydrodynamic compatibility conditions at curved porous-fluid interfaces in the lattice Boltzmann framework.

In this research, nanofibrous copper (0) was utilized as an efficient nanostructured catalyst in Azide-Alkyne Cycloaddition reaction, reduction of nitrobenzenes to anilines and reduction of aromatic aldehydes to benzyl alcohols. Nanofibrous copper was prepared via dealloying of Cu–Zn powder and was characterized by SEM, TEM, XRD, BET and EDS analyses. This catalyst produced very good results including high product yield, short reaction time and recyclability.

Bio-particles are usually considered as an elastic material, while it has been proven that these particles such as viruses and cells behave more like viscoelastic materials because of the liquid cytoplasm in cells and also the protein capsid around viruses; thus, this property is not ignorable because it leads to a non-precise prediction in simulations. On the other hand, the surface of these particles is usually considered smooth, while the topography shows asperities on them. In this paper, the viscoelastic contact model along with the asperities’ distribution of the bio-particles is considered near reality. Simulation results reveal that the prediction of the viscoelastic contact models is more precise and closer to the experimental data than the elastic state. Using experimental results and applying their effect, asperities’ radii are obtained and comparison shows that the rough viscoelastic theory is more accurate and closer to the experimental data in comparison with viscoelastic models without asperity. The simulation of the first phase of the manipulation, applying three states of the elastic, the viscoelastic, and the rough viscoelastic in addition to a comparison with similar modes, shows that in the particle’s sliding on the substrate, tip sliding on the particle, and the particle rolling modes, the critical force has the highest magnitudes in the rough viscoelastic, the elastic, and the viscoelastic, respectively. However, results for the critical time are different, i.e., the highest critical times are related to the elastic, the viscoelastic, and the rough viscoelastic states, respectively.

As promising biodegradable materials with nontoxic degradation products, magnesium (Mg) and its alloys have received more and more attention in the biomedical field very recently. Having excellent biocompatibility and unique mechanical properties, magnesium‐based alloys currently cover a broad range of applications in the biomedical field. The use of Mg‐based biomedical devices eliminates the need for biomaterial removal surgery after the healing process and reduces adverse effects induced by the implantation of permanent biomaterials. However, the high corrosion rate of Mg‐based implants leads to unexpected degradation, structural failure, hydrogen evolution, alkalization, and cytotoxicity. To overcome these limitations, alloying Mg with suitable alloying elements and surface treatment come highly recommended. In this area, open questions remain on the behavior of Mg‐based biomaterials in the human body and the effects of different factors that have resulted in these challenges. In addition to that, many techniques are yet to be verified to turn these challenges into opportunities. Accordingly, this article aims to review major challenges and opportunities for Mg‐based biomaterials to minimize the challenges for the development of novel biomaterials made of Mg and its alloys., Magnesium (Mg)‐based alloys have shifted into the focus as a new generation of degradable biomaterials for medical applications. Because biodegradable Mg‐based alloys possess excellent biocompatibility and unique mechanical properties, deploying these biomaterials eliminates the need for biomaterial removal surgery after the healing process and diminishes adverse effects induced by implantation of permanent implants. This article reviews the main challenges following the implantation of Mg‐based biomaterials in the human body. It also introduces a broad overview of opportunities to minimize the challenges for the development of advanced biomaterials made from Mg and its alloys.

In this study, 5 different electrospun chitosan-based scaffolds were fabricated for wound healing applications using benign solvents. Researchers have reported that chitosan/PEO scaffolds are generally unstable in aqueous solutions and have poor mechanical properties particularly in wet conditions, therefore we had to tackle these problems by modifying the scaffolds. The ratio of chitosan to PEO was equal in all of our scaffolds but they contained different amounts of cerium doped bioactive glass (Ce-BG). In a previous study performed by the same authors of this study, the morphology, structure, chemical bonding, cell biocompatibility, and cell cultures of the five scaffolds were analyzed. Meanwhile, the parameters studied in this study were antibacterial activity against gram-positive and gram-negative bacteria cells, mechanical properties, ion release behavior, and swelling properties. Results indicated that although increasing Ce-BG/CH (w/w) ratio up to 20% (w/w) improved the swelling degree and mechanical properties of the scaffolds significantly, increasing the ratio beyond 20% (w/w) reduced the useful effects of Ce-BG on the mentioned properties. The latter phenomenon was probably due to the agglomeration of Ce-BG nanoparticles. Even though the agglomeration of Ce-BG nanoparticles had some adverse effects, it did not affect the antibacterial activity and ion release behavior of the scaffolds. In fact, those properties continued to improve up to a ratio of Ce-BG/CH = 40% (w/w). It is worth noting, however, that increasing the Ce-BG/CH (w/w) ratio to 40% significantly improved the antibacterial activity of the scaffolds against gram-negative E. coli bacteria cells, but not against gram-positive S. aureus. Since none of the as-electrospun scaffolds had satisfactory mechanical properties in wet conditions, a modified sample was fabricated to enhance those properties. The modifications involved coating Ce-BGs nanoparticles with chitosan before inserting them into chitosan-polyethylene oxide electrospinning solutions. In the dried state, the modified sample had a 287% and 889% increase in tensile strength and an 88% and 330% increase in peak strain compared to the unmodified version of the sample and the base scaffold, respectively. Overall, the modified scaffold in its wet state had mechanical properties very close to the skin and its elongation at break was 28.6%, which was only 20% less than the required elongation at break for skin tissue scaffolds.

In this study, doped strontium fluorapatite (Sr-FAP) nanopowders were synthesised by sol-gel and used as a coating to modify Ti-6Al-4V substrates through CO2 laser cladding. The Ca ions of FAP wer...

In this study, the influences of the stress aging process on the electrochemical behaviors toward evaluating corrosion resistance of NiTi shape memory alloys in the in-vitro condition have been investigated. For this approach, the samples have been manufactured by introducing multiple precipitation morphology in the alloy structure via applying different levels of stresses during the aging process. The samples were characterized using multiply electron microscopy, electrochemical methods, X-ray diffraction, and differential scanning calorimetry. Results show that by prolonging aging time from 1 to 5 h and increasing the stress aging level (15–60-150 MPa) the corrosion resistance improves, which is implied a better formation of a protective layer. It seems that homogeneous precipitation of Ni-rich phases under the stress aging process improves the corrosion resistance of the alloy.

MXenes, a new family of two-dimensional (2D) transition metal carbides and nitrides, have received great research attention in diverse applications, including biomedicine, sensing, catalysis, energy storage and conversion, adsorption, and membrane-based separation, owing to their extraordinary physicochemical properties and various chemical compositions. In recent years, many surface functionalization strategies, such as surface-initiated polymerization and single heteroatom doping, have been cleverly developed to expand the potential of MXenes in different fields. This article reviews and puts into perspective the recent advances in MXene surface functionalization and various applications of the modified MXenes. The effect of surface functionalization on MXene properties (such as electronic, magnetic, mechanical, optical, and hydrophilicity/hydrophobicity) is discussed. Potential applications of pristine and functionalized MXenes in different fields are discussed. Finally, challenges and future directions in MXene surface modification are examined.

In this study, a series of electrospun chitosan/polyethylene oxide (PEO) nanofibrous scaffolds containing different amount of cerium-doped bioactive glasses (Ce-BGs) have been fabricated and proposed for tissue engineering applications. On a biological level, higher 8Ce-BG content significantly improved cytocompatibility of the scaffolds. Moreover, results of fibroblast cell culture study showed that greater 8Ce-BG content could enhance cell attachment and cell expansion on fiber mesh. Characterization of the scaffolds revealed that increasing 8Ce-BG content caused bioactive glass nanoparticles to agglomerate at a higher rate. The SEM mapping revealed thorough dispersion of submicrometric clusters in all areas of the polymeric matrix. Contact angle measurements showed that increasing 8Ce-BG/CH ratio from 0 to 10 (wt.%) improved wettability of the scaffold significantly. However, by increasing the ratio beyond 10 (wt.%), the wettability values decreased gradually. In conclusion, it was found that increasing 8Ce-BG/CH weight ratio up to 40 (wt.%) in the scaffold system was practical and useful for soft tissue engineering applications.

Grass shoot-shape silicon nanowires (SiNWs) with sharp tip have been successfully synthesized on an n-type Si (111) substrates at temperatures of 700 °C and various times using a thermal chemical vapor deposition (TCVD) technique. Au thin film (~10 nm thick) as catalyst were deposited on Si (111) substrates by a radio frequency magnetron sputtering system. Effect of the growth time on morphology of SiNWs has been reported. The morphologies, growth mechanism, homogeneity and crystalline structure of the nanowires were studied by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-ray diffractometer (XRD) and Raman spectroscopy. SEM images depict morphology of wires in form of nanoneedles (NNs) with base diameter of 60 nm, tip diameter of ∼5 nm and length up to 3 μm. TEM analysis revealed that the nanowires have core-shell structure with Au nanoparticles on the tip. Raman spectrum of as-grown SiNNs exhibited a transverse optical (TO) phonon mode. The obtained results have shown radius and length of the SiNNs increased with increase in growth time.

In this study, the free vibration of a composite sandwich plate reinforced with graphene nanoplatelets (GPLs) enclosed by piezoelectric layers is investigated using an analytical solution. In the framework of the first-order shear deformation plate theory, multilayer functionally graded graphene platelets-reinforced composite plate is assumed. Applying modified Halpin–Tsai model and rule of mixtures, the effective Young’s modulus, mass density and Poisson’s ratio of nanocomposites are predicted. In each individual layer, the weight fraction of GPL nanofillers illustrates a layer-wise variation along the thickness direction either uniformly or non-uniformly GPLs dispersed. Based on Maxwell’s equation, the electric potential in a piezoelectric layer is considered for open and closed circuit boundary conditions. Coupled governing equations of motion and boundary conditions are derived by using the Hamilton’s principle. Four auxiliary scalar functions are introduced to decouple the governing equations of motion and boundary conditions, which are solved analytically by employing Levy-type boundary conditions. The effects of GPLs weight fraction, GPLs distribution patterns, number of layers and aspect ratio are examined in detail. The results show that the best way to predict the most effective reinforcement is to distribute more GPLs with a larger surface area near the top and bottom surfaces of the plate. Besides, adding a small amount of GPLs as reinforcing nanofillers can significantly improve the stiffness of the plate.

The intrinsic brittleness of concrete in tension and shear is the principal reason for the weak performance of reinforced concrete (RC) connections under seismic loads. A viable way to overcome this challenge is the replacement of concrete in the joint area by Engineered Cementitious Composites (ECC) which typically show pseudo strain-hardening and multiple cracking behaviours. In the present study, at first, a finite element model to analyse RC/ECC connections is developed and validated by available experimental data. Then, the efficacy of using ECC in the joint area and the end part of the beam or column is investigated. The results show that the proposed model is acceptably able to predict the initial stiffness, the ultimate strength, and the cracking pattern of RC/ECC joints. By replacing ECC in the joint zone, the connection shows 27.5% and 52.6% increase in the ultimate strength and performance factor, respectively. Moreover, replacing concrete by ECC materials only in the vicinity of the joint zone is effective in enhancing the seismic performance of the connection. Although using ECC materials can enable one to reduce transverse reinforcements in the joint area, removing all stirrups in this area is not recommended when considering the results of this study.

Electrocatalyst support materials play significant role in the performance, durability and commercialization of fuel cells. This research work describes the preparation of metal oxide (nickel oxide (NiO), cobalt (Co) and copper (Cu) doped NiO) support materials on meshed titanium (Ti) substrate via a simple electro-deposition method for their application as novel support material for palladium (Pd) catalyst. Field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) techniques are employed to study morphology, composition and structure of fabricated electrodes, respectively. The electrocatalytic performance of fabricated electrodes toward ethanol oxidation reaction (EOR) in alkaline solution is examined by the cyclic voltammetry (CV), chronoamperometry (CA) techniques. Low peak potential (−0.2 V), increased peak current density (62.54 mA cm−2) and large electrochemical active surface area (16.02 m2 g−1) were remarkable properties of Pd/Cu–NiO/Ti electrode. The results of other electrochemical measurements, CO-striping voltammetry, long-term stability and electrochemical impedance spectroscopy (EIS) revealed that the Pd/Cu–NiO/Ti electrode has the privileged electrocatalytic performance for EOR relative to other prepared electrodes. Accordingly, the Pd/Cu–NiO/Ti can be considered as a hopeful electrode for ethanol electro-oxidation reaction in DEFCs.

In the present study, we investigate the effect of annealing temperature, annealing time, particle size, and impurity concentration on the oxidation behavior of the $${\mathrm{MgF}}_2$$ and $${\mathrm{MgF}}_2$$ - $${\mathrm{Cu}}$$ alloy powder. $${\mathrm{MgF}}_2$$ and $${\mathrm{MgF}}_2$$ - $${\mathrm{Cu}}$$ alloy samples have been prepared by mechanical alloying process. The samples have been annealed at different temperatures and times. The oxidation treatment of $${\mathrm{MgF}}_2$$ and $${\mathrm{MgF}}_2$$ - $${\mathrm{Cu}}$$ cermets in the air oven at different annealing temperature and time have been studied using XRD, SEM, and EDS. Our experimental results indicate that the oxidation rate increases by decreasing the particle size and increasing the annealing time. The results illustrates that the participation of copper material accelerates the oxidation reaction of $${\mathrm{MgF}}_2$$ .

Poloxamers, also called Pluronic, belong to a unique class of synthetic tri-block copolymers containing central hydrophobic chains of poly(propylene oxide) sandwiched between two hydrophilic chains of poly(ethylene oxide). Some chemical characteristics of poloxamers such as temperature-dependent self-assembly and thermo-reversible behavior along with biocompatibility and physiochemical properties make poloxamer-based biomaterials promising candidates for biomedical application such as tissue engineering and drug delivery. The microstructure, bioactivity, and mechanical properties of poloxamers can be tailored to mimic the behavior of various types of tissues. Moreover, their amphiphilic nature and the potential to self-assemble into the micelles make them promising drug carriers with the ability to improve the drug availability to make cancer cells more vulnerable to drugs. Poloxamers are also used for the modification of hydrophobic tissue-engineered constructs. This article collects the recent advances in design and application of poloxamer-based biomaterials in tissue engineering, drug/gene delivery, theranostic devices, and bioinks for 3D printing. STATEMENT OF SIGNIFICANCE: Poloxamers, also called Pluronic, belong to a unique class of synthetic tri-block copolymers containing central hydrophobic chains of poly(propylene oxide) sandwiched between two hydrophilic chains of poly(ethylene oxide). The microstructure, bioactivity, and mechanical properties of poloxamers can be tailored to mimic the behavior of various types of tissues. Moreover, their amphiphilic nature and the potential to self-assemble into the micelles make them promising drug carriers with the ability to improve the drug availability to make cancer cells more vulnerable to drugs. However, no reports have systematically reviewed the critical role of poloxamer for biomedical applications. Research on poloxamers is growing today opening new scenarios that expand the potential of these biomaterials from "traditional" treatments to a new era of tissue engineering. To the best of our knowledge, this is the first review article in which such issue is systematically reviewed and critically discussed in the light of the existing literature.

Shape memory alloys are increasingly used in numerous smart engineering structures. This study experimentally investigates static flexural and free vibration characteristics of composite beams reinforced with shape memory alloy wires. The key to this study is using shape memory alloy fibers as a means for influencing and tuning the static and dynamic responses of structures. A series of static three-point bending and modal experiments is performed to capture the capability of shape memory alloy wires in controlling the static and dynamic responses of a reinforced beam. Static and dynamic behaviors of the fiber-reinforced beam with different volumetric fiber fractions are examined. Before heat excitation, increasing the number of shape memory alloy wires leads to higher beam stiffness and lower beam deflection. However, with both heat activation and the higher number of shape memory alloy wires, beam deflection is significantly reduced. The modal vibration tests demonstrated that when shape memory alloy wires are not activated, the magnitude of natural frequencies slightly decreases by increasing the number of shape memory alloy wires. However, with heat excitation, the higher number of shape memory alloy wires, in contrast, increases the magnitude of natural frequencies. Furthermore, the higher number of activated shape memory alloy wires shows to predominantly increase the magnitude of higher modes of vibration rather than lower modes.

The challenges of interfacial defects and filler uniform dispersion are still preventing the design of mixed matrix membranes (MMMs) for the purpose of high gas selectivity. In this study, in-situ growth of UiO-66-NH2 on the external surface of carbon nanofibers (CNFs) resulted in the synthesis of a novel CNF/metal organic framework (MOF) composite which embedded into the pebax selective layer of thin-film nanocomposite (TFN) membrane. The uniform structure and defect-free interface was observed by FE-SEM analysis that reveals superior compatibility between polymer chains and CNF/UiO composite. Gas sorption analysis was investigated for pristine thin film composite (TFC) and TFN membranes and then the obtained experimental data were analyzed by Henry–Langmuir and Henry–Freundlich model. The results illustrated that gas permeation for the membranes followed the Henry–Freundlich model. Accordingly, synthesized TFN membranes demonstrated a higher CO2 permeability as well as proper CO2/CH4 selectivity compared to pristine TFC membrane. For instance, the pure and mixed gas permeation results of TFN membrane including 3 wt% of CNF/UiO composite represented a high CO2 permeability of around 328 (pure gas permeability) and 230 (mixed gas permeability) Barrer and CO2/CH4 selectivity of around 27 (ideal selectivity) and 21 (real selectivity) at feed pressure of 6 bar. Consequently, the TFN membranes exhibit exceptional separation performance in terms of overcoming the Robeson upper bound. The approach of decoration of MOFs on the surface of CNFs can be effective technique to enhance TFN membranes performance.

Theranostic platforms bring about a revolution in disease management. During recent years, theranostic nanoparticles have been utilized for imaging and therapy simultaneously. Zeolites, because of their porous structure and tunable properties, which can be modified with various materials, can be used as a delivery agent. The porous structure of a zeolite enables it to be loaded and unloaded with various molecules such as therapeutic agents, photosensitizers, biological macromolecules, MRI contrast agents, radiopharmaceuticals, near-infrared (NIR) fluorophores, and microbubbles. Furthermore, theranostic zeolite nanocarriers can be further modified with targeting ligands, which is highly interesting for targeted cancer therapies.

This paper reports on the simple synthesis of novel green magnetic nanoparticles (MNPs) with effective catalytic properties and reusability. These heterogeneous nanocatalysts were prepared by the anchoring of Co and V on the surface of CoFe2O4 nanoparticles coated with ascorbic acid (AA) as a green linker. The prepared nanocatalysts have been identified by scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray atomic mapping, thermogravimetric analysis, X-ray powder diffraction, vibrating sample magnetometer analysis, coupled plasma optical emission spectrometry and Fourier transform infrared spectroscopy. The impact of CoFe2O4@AA-M (Co, V) was carefully examined for NH2OH·HCl oximation of aldehyde derivatives first and then for the reduction of diverse nitro compounds with sodium borohydride (NaBH4) to the corresponding amines under green conditions. The catalytic efficiency of magnetic CoFe2O4@AA-M (Co, V) nanocatalysts was investigated in production of different aldoximes and amines with high turnover numbers (TON) and turnover frequencies (TOF) through oximation and reduction reactions respectively. Furthermore, the developed environment-friendly method offers a number of advantages such as high turnover frequency, mild reaction conditions, high activity, simple procedure, low cost and easy isolation of the products from the reaction mixture by an external magnetic field and the catalyst can be reused for several consecutive runs without any remarkable decrease in catalytic efficiency.

A composite of Ni nanoparticles incorporated in Kryptofix 22 conjugated magnetic nano-graphene oxide, CoFe2O4@GO–K 22·Ni, was synthesized via the grafting of Kryptofix 22 moieties on the magnetic nano-graphene oxide surface, followed by reaction of the nanocomposite with nickel nitrate. The Kryptofix 22 host material unit cavities can stabilize the Ni nanoparticles effectively and prevent their aggregation and separation from the surface. Characterization of the catalysts by FT-IR, FE-SEM, TGA, ICP, EDX, XRD, VSM and BET aided understanding the catalyst structure and morphology. This catalyst was efficiently applied for the synthesis of 1,4-benzodiazepine derivatives. The main advantages of the method are mild reaction conditions, inexpensive catalyst, it is environmentally benign, has high to excellent yields and shorter reaction times. This organometallic catalyst can be easily separated from a reaction mixture and was successfully examined for six runs with a slight loss of catalytic activity.

This paper reports a novel green procedure for immobilization of bimetallic Fe/Ni on amorphous silica nanoparticles extracted from rice husk (RH-SiO2). The heterogeneous nanocomposite (Fe/Ni@RH-SiO2) was identified using SEM, EDX, TEM, BET, H2-TPR, TGA, XRD, VSM, ICP-OES, and FT-IR analyses. The Fe/Ni@RH-SiO2 nanocomposite was applied as a powerful catalyst for the reduction of structurally diverse nitro compounds with sodium borohydride (NaBH4) in green conditions. This procedure suggests some benefits such as green chemistry-based properties, short reaction times, non-explosive materials, easy to handle, fast separation and simple work-up method. The catalyst was separated by an external magnet from the reaction mixture and was reused for 9 successive cycles with no detectable changes of its catalytic efficiency.

The study highlights the corrosion behavior of untreated and treatedtantalumwith addition of trimanganese tetraoxide (Mn3O4) nanoparticles in simulated inflammatory media. The anodic layer was produced on pure tantalum by anodization in electrolytes composed of ammonium fluoride, ethylene glycol, and water. Nanoparticles were deposited uniformly on the surface of the anodized tantalum with theelectrophoretic deposition(EPD) method. The results revealed that the anodic/EPD coating possessed more compactmicrostructureand higher bond strength than the anodic coating. Simulated inflammatory medium was based on phosphate-buffered saline with additions of H2O2and HCl. Potentiodynamic polarization andelectrochemical impedance spectroscopystudies showed that the anodic and Mn3O4layers protected the tantalum from corroding in an acidic inflammatory condition. Finally, thecorrosion protectionmechanism of Mn3O4NPs in inflammatory condition was presented.

A one-pot and facile method with assistance of high gravity was applied for the synthesis of inorganic two-dimensional MOF-5 embedded MXene nanostructures. The innovative inorganic MXene/MOF-5 nanostructure was applied in co-delivery of drug and gene, and to increase its bioavailability and interaction with the pCRISPR, the nanomaterial was coated with alginate and chitosan. The polymer-coated nanosystems were fully characterized, and the sustained DOX delivery and comprehensive cytotoxicity studies were conducted on the HEK-293, PC12, HepG2, and HeLa cell lines, demonstrating acceptable and excellent cell viability at both very low (0.1 μg.mL

An analytical solution has been developed developed in this research for electro-mechanical flexural response of smart laminated piezoelectric composite rectangular plates encompassing flexible-spring boundary conditions at two opposite edges. Flexible-spring boundary structure is introduced to the system by inclusion of rotational springs of adjustable stiffness which can vary depending on changes in the rotational fixity factor of the springs. To add to the case study complexity, the two other edges are kept free. Three advantages of employing the proposed analytical method include: (1) the electro-mechanical flexural coupling between the piezoelectric actuators and the plate’s rotational springs of adjustable stiffness is addressed; (2) there is no need for trial deformation and characteristic function—therefore, it has higher accuracy than conventional semi-inverse methods; (3) there is no restriction imposed to the position, type, and number of applied loads. The Linear Theory of Piezoelectricity and Classical Plate Theory are adopted to derive the exact elasticity equation. The higher-order Fourier integral and higher-order unit step function differential equations are combined to derive the analytical equations. The analytical results are validated against those obtained from Abaqus Finite Element (FE) package. The results comparison showed good agreement. The proposed smart plates can potentially be applied to real-life structural systems such as smart floors and bridges and the proposed analytical solution can be used to analyze the flexural deformation response.

A new analytical flexural solution based on double finite integral Fourier transform and trigonometric series differentiation procedures was developed for thick multi-layered composite hybrid rectangular plates resting on Winkler elastic foundation in air and water. The effect of material anisotropy, coupled hydro-mechanical loads, and underwater floor inclination angle,which were overlooked in the literature, is considered in this study. Furthermore, the predetermination of the shape deformation function is not required in our proposed analytical solution, which offers more accurate results. For the particular cases where the plate made of isotropic material is in air, the analytical results are compared with, and verified by the literature. Literature is lacking to investigate thick multi-layered composite hybrid rectangular plates with free edges and under hydro-mechanical load; hence our analytical results are compared with, and verified by,numerical analysis employing finite element method (FEM). The analytical results provide excellent agreement with both literature and the proposed FEM. FEM is shown to be time-intensive since the results converge after 60 seconds runtime with definition of 12159 elements during mesh refinement, yet the proposed analytical method demonstrates that the convergence can easily be achieved after 5 seconds runtime through selecting small values for Fourier terms.

The catalytic performance of Ni, Co, and Ni–Co-based catalysts on Al2O3 support are investigated in the dry methane reforming reaction. Besides, the influence of La or Y promoters on catalytic activity and structural properties of synthesized catalysts are examined in this paper. The prepared catalysts are characterized using N2 Adsorption/Desorption, FESEM, EDX, and XRD techniques. Higher average CH4 and CO2 conversions, as well as hydrogen yield, are obtained using Ni-Co catalyst with equal weight ratios. This could be the result of better dispersion of active sites according to the FESEM images and thus higher BET surface area of this catalyst compared with other un-promoted ones. Although the addition of La does not enhance the catalytic activity and structural properties of the 9Ni–9Co/Al2O3 sample, the presence of Y2O3 particles has a positive effect on both mentioned catalyst features. The maximum CH4 conversion of 99.39%, CO2 conversion of 92.38%, H2 yield of 86.20% and H2/CO molar ratio of 1.50 are achieved using 5Y–9Ni–9Co/Al2O3 at 700 °C. Besides, this catalyst shows lower deposited coke and higher stability compared with other promoted/un-promoted catalysts. The comparison between the activity of 5Y–9Ni–9Co/Al2O3 and industrial 18%Ni/Al2O3 during 11 h DRM shows that although 18%Ni/Al2O3 has higher conversions at first 9 h, its activity is decreased more than 5Y–9Ni–9Co/Al2O3 due to the coke deposition.

Introduction: Fabricating composite scaffolds with improved physicochemical properties as artificial microenvironments are of great interest in bone tissue engineering. Given advantageous properties of nano-hydroxyapatite/chitosan/gelatin (nHA/Cs/Gel) scaffolds, the present study aimed to synthesize a modified nHA/Cs/Gel biomimetic scaffold with improved features. Methods: Pure and copper (Cu)-substituted nHA was synthesized using the chemical precipitation method under controlled pH and temperature. Pure and Cu-substituted nHA/Cs/Gel scaffolds were fabricated by salt-leaching/freeze-drying method. Physicochemical characteristics of nanoparticles and scaffolds were explored using XRD, FTIR, FE-SEM/EDX, and ICP. Besides, scaffold mechanical strength, degradation, porosity, swelling, biomineralization, and cytocompatibility were assessed. Results: Pure and Cu-substituted nHA were synthesized and characterized with appropriate Cu substitution and improved physical properties. All scaffolds were highly porous (porosity >98%) and Cu incorporation reduced porosity from 99.555 ± 0.394% to 98.69 ± 0.80% while enlarged the pore size to more than100 µm. Cu-substitution improved the scaffold mechanical strength and the best result was observed in nHA.Cu5%/Cs/Gel scaffolds by the compressive strength 88.869 ± 19.574 MPa. Furthermore, 3% and 5% Cu-substituted nHA enhanced the scaffold structural stability and supported osteoblast spread, adhesion, survival, mineralization, and proliferation. Moreover, long-term and sustainable Cu release from scaffolds was observed within 28 days. Conclusion: Cu-substituted nHA/Cs/Gel scaffolds mimic the porous structure and mechanical strength of cancellous bone, along with prolonged degradation and Cu release, osteoblast attachment, viability, calcium deposition, and proliferation. Taken together, our results indicate the upgraded properties of nHA.Cu5%/Cs/Gel scaffolds for future applications in bone tissue engineering.

In this study, the combined effect of alumina nanoparticles concentration in diesel–biodiesel blended fuels and engine speed on the performance and emission characteristics of a six cylinder, four-stroke diesel engine was investigated. Alumina nanoparticles (40, 80, 120 and 160 ppm) were prepared and added as additive to the diesel–biodiesel blended fuel. A diesel engine was fueled with these blends and operated at different engine speeds (800, 850, 900, 950 and 1000 rpm). The interaction of variables on the emission and performance of the diesel engine was investigated afterwards through response surface methodology (RSM). The maximum values of brake power and torque were obtained as 42.82 kW and 402.8 N.m for nanoparticle concentration of 160 ppm and engine speed of 1000 rpm, respectively. Also, the minimum BSFC, CO and HC were measured as 207.21 gr/kWh, 1.15% and 9%, respectively. The maximum values of CO2 and NOx were recorded as 11.76% and 1899 ppm for nanoparticle concentration of 160 ppm and engine speed of 1000 rpm, respectively. Experimental results showed that alumina nanoparticle is a good addition for diesel–biodiesel blends to improve the performance and decrease the emissions of diesel engine. It was found that the developed mathematical model can be effectively used to predict the engine performance and emission.

The heterogeneity of the lamellar unit (LU) of arterial media plays an important role in the biomechanics of artery. Current two-component (fibrous component and a homogenous matrix) constitutive model is inappropriate for capturing the micro-structural variations in the LU, such as contraction/relaxation of vascular smooth muscle cells (VSMCs), fragmentation of the elastin layer, and deposition/disruption of the collagen network. In this work, we developed a representative volume element (RVE) model with detailed micro-configurations, i.e., VSMCs at various phenotypes, collagen fibers, and elastin laminate embedded in the ground substance. The fiber architecture was generated based on its volume fraction and orientations. Our multi-scale model demonstrated the relation between the arterial expansion and the micro-structural variation of the lamellar unit. The obtained uniaxial response of the LU was validated against the published experimental data. The load sharing capacity of fibrous component and VSMCs of the LU were obtained. We found that the VSMC could take 30% of the circumferential load when contracted until the collagen fibers were recruited, while this value was less than 2% for the relaxed VSMC. In addition, the contribution of collagen fibers at low stretch levels was negligible but became predominant when straightened in high stretches.Moreover, aging effects by collagen deposition was modeled to estimate the arterial stiffening. It was revealed that the aortic stiffness is mainly controlled by collagen fibers, instead of VSMCs. Our findings could shed some light about the contribution of VSMCs in arterial stiffness which has been under debate in recent years.

The purpose of this study is to evaluate the general function and properties of a new class of reinforced glass-ionomer cements (GICs). In this regard, GIC powders based on a molar composition of 4...

In this study, we first examined nanoparticles of Fe3O4 structures synthesized as magnet cores using simple hydrothermal method without surfactant, and at the next stage, we have prepared Zn-doped cadmium sulfide as dual shell. Therefore, doped-metal nanocomposites Fe3O4–Cds were produced and characterized by a rapid chemical process. The effects of concentration, temperature, and sediment factor on the morphology and particle size of the products were studied. The structure and morphology of products were studied using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and Fourier transform infrared spectrometer. A vibrating sample magnetometer was used to identify the ferromagnetic behavior of ferrite nanostructures. Also, to study the photocatalytic behavior of Fe3O4–Cds–Zn-doped nanocomposites, degradation of three azoic acids (acid black, acid blue, and methyl orange) was used under ultraviolet light. According to the results, the magnetic and photocatalytic function of these nanocomposites is clearly evident.

A wide variety of smart polymer systems such as thermosensitive polymers (TSPs)have been developed and applied mimicking nature. TSPs are a class of macromolecules that exhibit bio-inspired behavior and have various applications such as drug delivery, tissue engineering, theranostic particles and bioseparation. An inherent feature of a living system is its ability to react in response to an external stimulus. The temperature dependence of polymer properties is the reason behind dramatic changes in morphology, solubility, shape and sol-gel transition. TSPs can be synthesized as hydrogel, micro- and nanoparticles, film, micelle and mussel-inspired materials. The architecture of TSPs determines their biomimetic patterns and allows one to expand their uses. TSPs can be used as systems for the controlled release of drugs to a specific organ, as well as scaffolds in tissue engineering. Multi-responsive and thermosensitive features of TSPs give rise to design of smart systems for special applications. For example, pH- and photo-responsive abilities in combination with temperature sensitivity can play a vital role in drug delivery and tissue engineering. In-depth knowledge about the structure-property relationship is a key factor to design a smart biomimetic polymer. In this review paper, the functional design of the TSPs, their biomedical applications and the road ahead for their developments are comprehensively overviewed. Fil: Zarrintaj, Payam. Urmia University; Irán. Amirkabir University Of Technology; Irán Fil: Jouyandeh, Maryam. University Of Tehran; Irán Fil: Reza Ganjali, Mohammad. Biosensor Research Center; Irán. University Of Tehran; Irán Fil: Shirkavand Hadavand, Behzad. Institute For Color Science And Technology; Irán Fil: Mozafari, Masoud. Iran University Of Medical Sciences; Irán Fil: Sheiko, Sergei S.. University of North Carolina; Estados Unidos Fil: Vatankhah Varnoosfaderani, Mohammad. University of North Carolina; Estados Unidos Fil: Gutiérrez Carmona, Tomy José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina Fil: Reza Saeb, Mohammad. Institute For Color Science And Technology; Irán. University Of Tehran; Irán

A three-dimensional rate independent inelastic constitutive model has been developed to predict the fatigue behavior of metals spanning low to high cycles, based solely on the monotonic stress strain curve and a cyclic test for a few cycles (

In order to promote bone healing, new generations of biomaterials are under development. These biomaterials should demonstrate proper biological and mechanical properties preferably similar to the natural bone tissue. In this research, 3D-printed barium strontium titanate (BST)/β-tricalcium phosphate (β-TCP) composite scaffolds have been synthesized as an alternative strategy for bone regeneration to not only induce appropriate bioactive characteristics but also piezoelectric behavior. The physical, chemical and biological performance of the scaffolds have been examined in terms of mechanical, dielectric properties, apatite-forming ability, Alizarin Red Staining (ARS), Alkaline Phosphatase activity (ALP), and cytotoxicity. The samples composed of 60% BST and 40% β-TCP showed the highest compressive strength, bending module, elastic modulus and the Young's modulus. The dielectric constant increased with further addition of the BST phase in the constructs. Scanning Electron Microscope (SEM) and energy dispersive X-ray (EDX) analyses showed that 60% BST/40% β-TCP sample had the highest amount of bone-like apatite formation after 28 days in simulated body fluid (SBF). Moreover, the results of ARS proved that 60% BST/40% β-TCP composite could present higher quantities of mineral deposition. The ALP activity of osteosarcoma cells on 60% BST/40% β-TCP sample showed higher activities compare with the other composites. None of the samples demonstrated any sign of toxicity using MTT test. It can be suggested that BST/β-TCP composite scaffolds can be potentially used as the next generation of bone tissue engineering scaffold materials.

The average evaporation in Iran is 3 times higher than the world average. Applying chemical monolayers on water surfaces is one of the promising methods for suppressing the evaporation. Literature studies have shown that the mixture of cetyl and stearyl (ratio of 1 to 9) is the state-of-the-art monolayer to minimize the evaporation. Adding calcium hydroxide increases the spreading rate and self-healing of the monolayer. Despite long study and investigation on monolayers, there are inconsistencies in explaining the mechanism by which monolayers decrease the evaporation. The mechanisms used to explain the evaporation reduction are: (i) increasing the reflected solar radiation, (ii) dampening the waves formed by winds and decreasing the water surface area, consequently, and (iii) limiting the escape of water molecules. In this paper, by design of experiments (DOE), we try to answer the above question. Evaporation rate from a container in absence of wind or low wind (~0.2 m/s) and at moderate temperature and relative humidity (~20 °C and 45%) is ~ 10 mm/day. Utilization of the monolayer can save 41% of the evaporated water. Also, in absence of radiation, a 9 m/s wind caused ~ 15 mm/day evaporation. By increasing the wind speed from 0 to 9 m/s, effectiveness of the monolayer deteriorated from 60 to 13%. Therefore, the main mechanism is neither reflecting the radiation (as in absence of radiation, monolayer was still effective) nor dampening the waves and decreasing the surface area (as in absence of wind, monolayer was effective; also, at higher wind speeds where the surface area increases, monolayer efficiency decreases). Therefore, the main mechanism by which monolayers decrease the evaporation rate is limiting the escape of water molecules. So, monolayers may be effective even during the nights even though radiation is at its lowest.

Small-diameter vascular grafts (SDVGs) are associated with a high incidence of failure due to infection and obstruction. Although several vascular grafts are commercially available, specific anatomical differences of defect sites require patient-based design and fabrication. Design and fabrication of such custom-tailored grafts are possible with 3d-printing technology. The aim of this study is to develop 3d-printed SDVGs with a nitric oxide (NO)-releasing coating to improve the success rate of implantation. The SDVGs were printed from polylactic acid and coated with blending of 10 wt% S-nitroso-N-acetyl-D-penicillamine into the polymeric substrate consisting of poly (ethylene glycol) and polycaprolactone. Our results show that NO is released in the physiological range (0.5-4 × 10-10 mol·cm-2·min-1) for 14 days and NO-releasing coating showed significant antibacterial potential against Gram-positive and Gram-negative strains. It was shown that both NO-releasing and control grafts are biocompatible in-vitro and in-vivo. Interestingly, the NO-releasing SDVGs dramatically enhanced ECs proliferation and significantly enhanced ECs migration in-vitro compared to control grafts. In addition, the NO-releasing SDVGs showed angiogenic potential in-vivo which can further prove the results of our in-vitro study. These findings are expected to facilitate tissue regeneration and integration of custom-made vascular implants with enhanced clinical success. STATEMENT OF SIGNIFICANCE: A series of 3d-printed small-diameter vascular grafts (SDVGs

The vibration and stability analyses of functionally graded (FG) reinforced porous plates with piezoelectric layers under supersonic flow are investigated. The plate has a FG core reinforced by nanocomposite graphene platelets (GPLs) which surrounded by two piezoelectric layers. The GPLs are distributed thorough the thickness direction both uniformly and non-uniformly. The first-order shear deformation plate theory (FSDT) and first-order piston theory are applied to analyze the stability of FG porous plates. Using Hamilton's principle and Maxwell's equation, the governing equations of motion as well as electrical and mechanical boundary conditions are obtained. Applying the Galerkin approach, the partial differential governing equations are converted to the ordinary differential equations. The numerical results show that the flutter aerodynamic pressure and natural frequencies decrease as the porosity coefficient increases. Besides, the symmetric porosity distribution together with GPL pattern A predicts the highest flutter aerodynamic pressure and natural frequencies. Also, the best efficient way to increase the stability region is considering GPL pattern A, with dispersing more GPLs fillers near the top and bottom surfaces of FG porous plate along with symmetric porosity distribution. Furthermore, FG porous plate enclosed by piezoelectric layers in open circuit condition predicts higher flutter aerodynamic pressure and natural frequencies than similar plate in closed circuit condition.

Magnesium (Mg) particle has been recently introduced in a poly- l -lactic acid (PLLA) matrix to enhance to its mechanical properties. The coating of Mg particle could also regulate its degradation rate. In this work, the mechanical behavior of PLLA/Mg composite was characterized using a three-dimensional representative volume element (RVE) model. The influences of Mg weight fraction, imperfect bonding between particle and polymer matrix, and the interphase layer on the mechanical behaviors of the composites were quantified. Results clearly demonstrated that the effective Young's modulus and yield strength of the composite were enhanced by the Mg particles, as well as its MgO coating. In addition, the imperfect interfacial bonding between the Mg particle and PLLA weakened the mechanical advantage of the composite, which was in good agreement with the documented experimental observations. This work might shed some light on the optimal design and manufacturing of the bioresorbable composites.

In the present work the corrosion behavior and in-vitro bioactivity of two kinds of porous Mg-metal matrix nano-composites separately reinforced with Al2O3 whiskers and Si3N4 particles were reported. 10 wt% of reinforcement was mixed with magnesium using high-energy ball milling and ethanol media for 10 min. After that, 10 ml ethylene glycol was added to milled mixture at the final stage of drying on a heater/stirrer at 70 °C. After stirring for 12 h, the powder mixtures were uniaxially pressed at 300 MPa to produce bar-shaped green specimens. The microwave sintering was performed at 650 °C without soaking time in a graphite bed. Porosity of about 50% was measured for both sintered composites using Archimedes principle. The XRD investigations revealed Mg2Al3 and MgO phases as the result of reaction between Mg and Al2O3. Moreover, the reaction products in Mg- Si3N4 composite were Mg2Si, Mg3N2 and Si. The corrosion tests showed that the polarization resistance of both prepared composites is higher than that of pure Mg. Mg-Al2O3 composite also showed lower corrosion current density compared to Mg- Si3N4 composite (1.42E−4 and 1.36E−3 A cm−2, respectively). In-vitro bioactivity analysis of composites showed high level of needle-shaped CA-P inside porosities of Mg-Si3N4 composite; while in the case of Mg-Al2O3 composite a lower amount and smaller needle-shaped particles were found.

Intelligent ferrogels (consist of a functional hydrogel incorporating magnetic nanoparticles (NPs)) have attracted extensive attention due to their special properties, making them promising for biomedical applications. Controlled drug delivery systems alongside magnetic fluid hyperthermia are the most important applications of these ferrogels. In present work, manganese-zinc ferrite NPs were synthesized by thermal decomposition method. Hydrogel were produced with different percetage of acrylic acid and acrylamide. The NPs were coated with the optimized thermoresponsive copolymer N-isopropylacrylamide co-acrylic acid co acrylamide P(NIPAAm-4%AAc-8%AAm) by mini-emulsion method. Doxorubicin (DOX) was loaded into the ferrogel and the drug release profiles were plotted in different temperatures. Specific absorption rate (SAR) value was used to evaluate the hyperthermal efficiency of the ferrogel. The results showed that the synthesized NPs were single phase spinel with narrow size distribution. The average NPs size was reported about 10 nm. The Nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopy analyses confirmed the accurate formation of the copolymer. Ultraviolet–visible (UV–visible) spectrophotometry results illustrated that the lower critical solution temperature (LCST) of the hydrogel was increased from 32.5 to 39.2 °C, because of copolymerizing the NIPAAm monomer with hydrophilic monomers (AAm and AAc). The drug release study of the ferrogel samples in different temperatures showed that the drug release profile was significantly increased above LCST, because of the dehydration of thermo-responsive copolymer chains.

MgO/ZnO composite coatings were successfully prepared on AZ91 Mg alloy by plasma electrolytic oxidation (PEO) method using electrolytes containing ZnO nanoparticles (NPs) to extend their biomedical applications. The effect of the concentration of 0 to 4.5 g·L−1 ZnO NPs in phosphate-based electrolyte on the microstructure, composition, physical features, corrosion and biodegradation properties of coatings was investigated. Observing the microstructure through field emission scanning electron microscopy (FESEM) confirmed that ZnO NPs were well up-taken in the coating structure with crater-like morphology and, they were mostly accumulated near the pores. As ZnO NPs concentration increased, more particles were incorporated in the coating; however, porosity, thickness and surface roughness reduced. The evaluation of the electrochemical behavior of specimens using potentiodynamic polarization test revealed that the polarization resistance of the samples increased from 9.26 to 683.2 kΩ·cm2 by adding 4.5 g·L−1 ZnO NPs. The study of corrosion mechanism by identifying the coating features using electrochemical impedance spectroscopy (EIS) indicated that the compacting of the coating and the difficulty of the penetration path of corrosive ions between the coating layers due to the presence of ZnO NPs had a more dominant effect relative to thickness reduction. Conducting the bioactivity test by immersion of coatings in simulated body fluid (SBF) solution for 14 days showed the higher growth of calcium phosphate layer formed on the sample as the concentration of ZnO NPs increases. In addition, the changes in weight loss and volume of hydrogen evolution were much less, and the mechanism of these changes was presented.

In the present study, the wear behavior of ultra-fine grained (UFG) Al-Mg alloys produced by a severe plastic deformation (SPD) method was assessed and compared against the annealed coarse-grained alloy. To this end, weight loss, wear resistance, friction coefficient, and morphology of the worn surfaces was investigated. Constrained groove pressing-cross route (CGP-CR) process, an SPD technique, was implemented at ambient temperature up to two passes to impose an equivalent plastic strain of about 4.64. Formation of a UFG structure with an average sub-grain size of ~ 350 nm with an enhanced tensile strength of up to ~ 225 MPa and indentation hardness of up to ~ 95 HV were achieved upon two passes of CGP-CR process. The pin-on-disk dry wear sliding testing was conducted up to a distance of 1000 m under normal loads of 5, 7, and 9 N at a constant sliding speed of 0.5 m/s. The trends measured for the evaluation of wear properties/mechanisms are discussed based on the microstructural features and mechanical property of UFGed alloys. The results showed that by employing the CGP-CR process and through the formation of UFG structure, the wear resistance was considerably increased. This was even beyond two times (~ 100%) larger depending on the normal loading with the lowest coefficient of friction around 0.6. Observation and study of the morphology of the worn surfaces under field emission-scanning electron microscopy (FE-SEM) revealed a change in the wear mechanism from sticking followed by formation of plastic deformation bands and delamination in the coarse-grained annealed alloy into a combined abrasive-adhesive behavior in the UFG material.

Hypoxia is one of the major challenges after scaffold implantation which can lead to cell necrosis and bacterial infection. Using of supplemental oxygen can increase the cell proliferation, encourage the cell differentiation and prevent the infections. Developing an engineered scaffold with a sustained oxygen release is an outstanding way for addressing the challenges of oxygen deficiency. In this study, the bioceramic scaffolds were fabricated from biphasic calcium phosphate (BCP) powder with the composition of 60% hydroxyapatite (HA) and 40% beta-tricalcium phosphate (β-TCP). The Robocasting technique was utilised for producing a porous structure comprising interpenetrated ceramic rods in a 3-dimensional tetragonal mesh. The scaffold was modelled by the finite element method (FEM) for computing the stress fields and predicting their mechanical performance. Calcium peroxide (CPO), as an oxygen-producing and antimicrobial biomaterial, was mixed with a polycaprolactone (PCL) solution and was coated on the scaffolds by the dip-coating method. The coating layer possessed three different percentages of CPO (1, 3 and 5 wt%). The oxygen-releasing profile proved that this design of coating-scaffold could be effective as a system of oxygen delivery. According to the antibacterial investigations, releasing of CPO from the scaffolds could inhibit the growth of E. coli and S. aureus. SBF tests confirmed that the coated scaffolds because of CPO particles on their surface presented superior apatite precipitation in comparison with the uncoated one. The differentiated osteoblastic function was monitored by measuring the alkaline phosphatase (ALP) activity. The coated BCP scaffolds with 3% and 5% CPO exhibited higher ALP activity compared to the other samples. The results demonstrated that the proposed bioceramic-based scaffolds containing oxygen-generating coating could be optimised to supply an antibacterial performance, ideal mechanical properties, improved ALP activity and higher apatite formation ability. Therefore, these scaffolds can be a promising candidate for applying in bone tissue engineering.

Synthesis and use of novel compositions of bioactive glasses (BGs) for hard tissue engineering are of important significance in the biomedical field. In this study, we successfully synthesized a series of 58S-based BGs containing fluoride (F−) and silver (Ag+) ions through a sol-gel method for possible use in bone/dental regeneration and antibacterial strategies. Characterizations of samples were performed by using thermal analyses (thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC)), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), textural analysis (N2 adsorption-desorption), and morphological observations by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The obtained data revealed that the fabricated BGs are in a glassy state before incubation in the Kokubo’s simulated body fluid (SBF), and an apatite-like layer is formed on their surface after 7 days of immersion in SBF. The size of the glass particles was in the nano-range (about 100 nm or below), and their pore size was in the mesoporous range (15-25 nm). These early results suggest that the F- and Ag-doped glasses show promise as multifunctional bioactive materials for bone/dental tissue engineering.