Showing 93 results for Ali
Elham Ghasemi, Majid Tavoosi, Ali Ghasemi, Mohammad Loghman Estarki,
Volume 20, Issue 2 (June 2023)
Abstract
In the present study, the structural and magnetic characteristics of Fe-Co-Cr system, with 28 at. % of Cr content, during casting, solutioning and thermo-magnetic treatment has been investigated. Based on results, the formation of single α-phase solid solution in the Fe72-xCoxCr28 (10The Co content had negligible effects on magnetic characteristics of Fe62Co10Cr28, Fe60Co12Cr28 and Fe58Co14Cr28 alloys. Fe72-xCoxCr28 (10 with a constant Cr content of about 28 at. %, were outside the miscibility gap in the equilibrium phase diagram, and therefore TMT had no effect on the final magnetic properties.
Mohammad Molaahmadi, Majid Tavoosi, Ali Ghasemi, Gholam Reza Gordani,
Volume 20, Issue 2 (June 2023)
Abstract
Investigation the structural and magnetic properties of nanocrystalline Co78Zr17B2Si1W2 alloy during melt spinning and annealing processes were the main goal of this study. In this regard, samples were prepared using vacuum induction melting, melt spinning and subsequent annealing. The specimens were evaluated using X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), differential scanning calorimetry (DSC) and vibrating sample magnetometer (VSM). Based on results, nanocrystalline Co5Zr single phase with hard magnetic properties (Ms=29.5 emu/g and Hc=2.7 kOe) successfully formed during melt spinning process (at wheel speed of 40 m.s-1). The coercivity value of rapid solidified sample increased to about 3.2 kOe during annealing process up to 400°C. However, more increasing in annealing temperature lead to the transformation of non-equilibrium magnetic Co5Zr phase to stable Zr2Co11 phase, which has distractive effects on final magnetic properties.
Zahra Shamohammadi Ghahsareh, Sara Banijamali, Alireza Aghaei,
Volume 20, Issue 2 (June 2023)
Abstract
Various analysis techniques were used to investigate the effects of P2O5 on the crystallization, mechanical features, and chemical resistance of canasite-based glass-ceramics. The results showed that canasite-type crystals were the primary crystalline phase in the examined glass-ceramics subjected to the two-step heat treatment, while fluorapatite was the secondary crystalline phase in some specimens. The microstructural observations by field emission electron microscope indicated that the randomly oriented interlocked blade-like canasite crystals decreased with an increase in the P2O5 content of the parent glasses. Among the examined glass-ceramics, the Base-P2 composition (containing 2 weight ratios of P2O5 in the glass) showed the most promising mechanical features (flexural strength of 176 MPa and fracture toughness of 2.9 MPa.m1/2) and chemical resistance (solubility of 2568 µg/cm2). This glass-ceramic could be further considered as a core material for dental restorations.
Ali Hasanzade Salmasi, Mahban Zarei, Shadab Safarzadeh Khosroshahi, Soolmaz Heidari, Farhood Najafi, Mojtaba Ghomayshi, Katayoun Lesani,
Volume 20, Issue 3 (September 2023)
Abstract
Amorphous calcium phosphate (ACP) which is a transient phase in natural bio-mineralization process has recently gained the spotlight. This study aimed to assess the effect of incorporation of nano-ACP (NACP) in a dental adhesive with/without surface treatment with silane coupling agent on bond strength. NACP was synthesized by the wet chemical precipitation technique. To characterize the structure of NACP, X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy were used. Forty molars were randomized into 4 groups of 10. The teeth were restored with composite resin and the bonding agent (one of the four groups). Adper Single Bond 2 was used as the control group. In 4wt% NACP group, NACP fillers were added to the bonding agent. In 0.4wt% and 4wt% SNACP groups, silanized NACP fillers were added to the bonding agent. Finally, the mode of failure of specimens was determined. Data were analyzed by one-way ANOVA and Tukey's post-hoc tests. P<0.05 was considered statistically significant. Addition of 4wt% non-silanized NACP decreased the bond strength compared with the control group (P<0.05). The bond strength of the groups with silanized fillers was not significantly different from that of the control group. Addition of silanized NACP to dental adhesive had no significant adverse effect on bond strength, which is a promising finding to pave the way for the synthesis of bonding agents containing bioactive fillers.
Nailia Rakhimova, Vladimir Morozov, Aleksey Eskin, Bulat Galiullin,
Volume 20, Issue 3 (September 2023)
Abstract
Salihah Alkhobrani, Hossein Bayahia, Fares T. Alshorifi,
Volume 20, Issue 3 (September 2023)
Abstract
In this study, CoFe2O4 (CoF) and ZnFe2O4 (ZnF) photocatalysts were successfully prepared by a facile and simple chemical precipitation method for degradation of methylene blue (MB) and methyl orange (MO) dyes under direct sunlight irradiation. The obtained ferrites were then characterized through XRD, TEM, EDS, UV-vis, and SEM. XRD and TEM results exhibited cubic nanostructures with sizes ranging from 9 to 16 nm and 11 to 18 nm for ZnF and CoF, respectively. SEM images showed homogenous, porous flat surfaces. EDS spectra confirmed the successful synthesis of ZnF and CoF nanostructures with high purity. UV-vis spectra results of MB and MO dyes showed maximum sunlight absorbance in the absence of ZnF and CoF, while a regular decrease in the sunlight absorbance was observed in the presence of ZnF and CoF within 15-60 min. The UV-vis results also showed that ZnF had higher photocatalytic activity than CoF. The experimental findings showed that the highest % degradation was 92.89% and 96.89% for MO and MB dyes, respectively, over ZnF compared to CoF photocatalyst (87.55% and 88.41% for MO and MB, respectively). These findings confirm that porous ZnF and CoF nanostructures are critical in promoting the degradation of dyes under sunlight instead of UV-vis light lamps that consume/require electrical energy.
Assist. Prof. Dr. Saad Mahmood Ali,
Volume 20, Issue 4 (December 2023)
Abstract
In the present work, development models of a new artificial human soft heart and artificial heart valves using nanocomposite materials and synthetics were designed, manufactured, and tested. The fabricated mechanical artificial heart valves were examined to determine the best service life for each type. The fatigue life results were implemented by using the transient repeated and continuously applied blood pressure on each produced value to simulate diastolic and systolic that occur in the natural heart at each pulse cycle. The obtained results showed that a 3D printing of a new generation soft artificial heart for a permanent replacement was implemented as an alternative to the high-cost available temporary implant mechanical hearts, which may exceed the price by tens and hundreds of thousands of dollars, with a working life of not more than five years. The obtained fatigue safety factors for the produced artificial valves using different materials and designs were decreased with the complexity of the movement of the moving parts of the valve. The highest rates were obtained when using the valves with flat, simple movement in one direction like the single-leaflet type valve, where all the used materials are suitable for the production of this type of valve. The highest obtained safety factor was reached (15). The lowest rates were recorded when using the highly flexible and strong PSN4 nanocomposite material for fabricating the mitral tri-leaflet valve (thick. = 1.0 mm) reached 1.91. This value decreases to 0.99 when using the same type and material of valve but with a thickness equal to 0.5 mm. It can be noted here that the only suitable for the manufacture of this artificial valve type is the nanocomposite polyetherimide/ silicone rubber with nano silica (PSN4), whereas the other used materials failed because the fatigue factor values are less than 1. The service life span of this material is about 9200 x 106 cycles, which is equivalent to about 290 years, followed by SIBSTAR 103 with a default age of 209.6 x 106 cycles or 9 years.
Bahram Azad, Ali Reza Eivani, Mohammad Taghi Salehi,
Volume 20, Issue 4 (December 2023)
Abstract
Microstructure evolution and mechanical properties of Zn-22Al alloy after post-ECAP natural/artificial aging were investigated. A homogenization treatment was applied to the casting samples. In addition, after preparing the samples for the ECAP, secondary homogenization treatment was done and then the samples quenched in the water to form a fine grain structure. After 8 passes of ECAP, some ECAPed samples were naturally aged and some ECAPed samples were artificially aged. Natural aging after 8 passes of ECAP showed that Zn-22Al alloy has a quasi-stable microstructure because limited grain growth occurred. Two-phase structure of Zn-22Al alloy prevented excessive grain growth after natural aging. On the other hand, artificial aging after 8 passes of ECAP caused a relatively much grain growth took place. In shorter times of artificial aging, the grain growth rate is faster due to the high surface energy of grain boundaries. On the contrary, as the time of artificial aging increased, the surface energy of grain boundaries decreased, which leads to a decrease in the grain growth rate. In addition, texture evolution was studied after aging artificial. Therefore, the main texture of α and η phases was determined.
Ali Hosseinian Naeini, Seyed Ali Hosseini Moradi,
Volume 20, Issue 4 (December 2023)
Abstract
The growth of industries, populations, and industrial activities includes environmental pollutants. Pollution causes problems such as reduced light transmission, anaerobic conditions, and complications such as allergies and cancer for humans and other living organisms. The adsorption method is one of the most attractive, and efficient methods for removing environmental pollutants such as pharmaceuticals. Among the standard methods for wastewater treatment, adsorption is more efficient than other methods and is more economical. They have a meager price. Adsorption of pollutants can be an excellent way to remove toxic substances from polluted waters and industrial effluents. In this review, pharmaceutical removal by adsorption process was reviewed in details.
Amruta Patil, Sonali Mahaparale,
Volume 21, Issue 1 (March - Special Issue 2024)
Abstract
Iron oxide nanoparticles has attracted extensively due to their supermagnetic properties, preferred in biomedicine because of their biocompatibility and potential nontoxicity to human beings. Synthesis of iron nanoparticles (FeNPs) was prepared with the help of ferric chloride and ferrous sulphate by using the coprecipitation method. The variation and combination of ferric and ferrous concentrations affect the physical and magnetic properties of iron oxide nanoparticles. The effect of 0.1 M ferric and ferrous concentration on iron oxide nanoparticles studied separately and in combination. The obtained nanoparticles were characterized by Particle size, zeta potential, Ultraviolet (UV-visible), Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), Scanning electron microscope (SEM), Thermal gravimetric analysis (TGA), and Vibrating-sample magnetometer (VSM) techniques. Particle size was below 200nm and zeta potential was within the limit for all the batches. UV visible spectra at 224 nm, and FTIR exhibit two peaks at 510 and 594 cm-1, indicating iron oxide NPs and XRD confirmed the crystalline nature of Fe. SEM showed a spherical shape for all batches. The use of a combination of ferric and ferrous is more effective than its individual use. TGA and VSM studies confirmed its magnetic properties.
Dipali Potdar, Sushant Patil, Yugen Kulkarni, Niketa Pawar, Shivaji Sadale, Prashant Chikode,
Volume 21, Issue 1 (March - Special Issue 2024)
Abstract
The Nickel tungsten (Ni-W) alloy was electrodeposited on stainless steel (SS) substrate using potentiostatic mode at room temperature. Potentiostatic electrodeposition was carried out by varying the deposition time. The physicochemical properties of Ni-W alloys were studied using X-Ray diffraction (XRD), Electron Microscopy and micro-Raman spectroscopy. Recorded XRD spectra was compared with standard JCPDS card and the presence of Ni was confirmed, no such peaks for W were observed. Further study was extended for micro-Raman analysis. From Raman spectroscopy study the appearance of Ni-O and W6+=O bonds confirms that the Ni-W present in amorphous phase. Several cracks were observed in SEM images along with nanoparticles distributed over the electrode surface. The appearance of cracks may be correlated with the in-plane tensile stresses, lattice strains and stacking faults and may be related to the substrate confinements.
Yugen Kulkarni, Niketa Pawar, Namrata Erandole, Muskan Mulani, Mujjamil Shikalgar, Swapnil Banne, Dipali Potdar, Ravindra Mane, Smita Mahajan, Prashant Chikode,
Volume 21, Issue 1 (March - Special Issue 2024)
Abstract
The paper investigates the solar photodegradation of Methylene Blue dye using copper oxide (CuO) thin films synthesized by the Successive Ionic Layer Adsorption and Reaction (SILAR) method. The structural, morphological, and optical characteristics of the CuO thin films have been investigated by employing a variety of methods, such as Fourier transform Infrared (FTIR) spectroscopy, UV-Vis spectroscopy, Scanning electron microscopy (SEM), and X-ray diffraction (XRD). The outcomes showed that CuO thin films with excellent surface shape and a highly crystalline nature had been successfully deposited. Methylene Blue was subjected to solar radiation during its photodegradation process, and the outcomes showed a significant decrease in the dye's concentration over time. To maximize the photo degradation process, the effects of other experimental factors were also assessed, such as the starting concentration of MB, the quantity of CuO thin film, number of SILAR cycles and the pH of the solution. Good photocatalytic activity is demonstrated by CuO thin films produced using the SILAR approach in the solar photodegradation of methylene blue. The development of affordable and ecologically friendly wastewater treatment technology that can use sun energy to break down persistent organic contaminants is affected by these findings.
Avinash Ramteke, Pradnya Chougule, Pranali Chavan, Amit Yaul, Gourav Pethe,
Volume 21, Issue 1 (March - Special Issue 2024)
Abstract
Nickel doped CoMn ferrites with high magnetization were synthesized by double sintering solid state route with compositions of Co0.7-xNixMn0.3Fe2O4 with x = 0, 0.05, 0.1 and 0.15. Theoretical Cation distribution for cubic spinel ferrites was suggested on basis of electrical configuration expectations and cation site preferences. Cation distribution suggested was in good agreement with experimental results obtained from VSM and XRD. Values of theoretically calculated magnetic moment, coercivity and magnetization are in good agreement with experimental data obtained from VSM. Maximum saturation magnetization of 37.7emu/gm is obtained for sample Co0.7Mn0.3Fe2O4 at magnetic field of 5K Oe. Magnetostriction was found to increase with increasing magnetic field (from 1KOe to 5KOe.) Maximum magnetostriction of 84ppm was observed for sample Co0.7Mn0.3Fe2O4 at 5KOe. Maximum magnetization of magnetoelectric composites with 30% Co0.7-xNixMn0.3Fe2O4 – 70% PbZr0.48Ti0.52 was found to be 7.4 emu/g for composition with x = 0.
Amit Bandekar, Pravin Tirmali, Paresh Gaikar, Shriniwas Kulkarni, Nana Pradhan,
Volume 21, Issue 1 (March - Special Issue 2024)
Abstract
The Mn-Zn ferrite with a composition of Mn0.25Mg0.08Cu0.25Zn0.42Fe2O4 has been synthesized in this study using the chemical sol-gel technique at a pH of 7. The sample was prepared and subsequently annealed at a temperature of 700°C. The nanocrystalline ferrite samples were subjected to characterization using X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), Thermogravimetry (TG), and Differential thermal analysis (DTA). The findings of these observations are delineated and deliberated. The sample's phase composition was verified using X-ray diffraction examination. The crystalline size was determined using Scherrer's formula and was observed to be within the range of 20-75 nm. Two notable stretching bands were seen in the FTIR spectra within the range of 400-650 cm-1. The spinel structure of the produced nanoparticles was confirmed by these two bands. The magnetic characteristics of the powder were examined using a Vibrating Sample Magnetometer (VSM). The presence of M-H hysteresis loops suggests that the produced nanoparticles have superparamagnetic properties, as evidenced by their low coercive force, remanent magnetization, and saturation magnetization values.
Mohammad Derakhshani, Saeed Rastegari, Ali Ghaffarinejad,
Volume 21, Issue 2 (June 2024)
Abstract
In this research, a nickel-tungsten coating as a catalyst for hydrogen evolution reaction (HER) with different current densities was synthesized and the resulting electrocatalytic properties and morphology were assessed. Linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS), and chronoamperometry in 1 M NaOH were used to evaluate the electrocatalytic activity for HER. By increasing the current density of electrodeposition up to 500 mA/cm2, a columnar morphology was observed. The cyclic voltammetry test (CV) revealed that when the plating current density increases, Cdl has increased from 248 to 1310 µF/cm2 and the active surface area increases 5 times. The results showed that by modifying the coating morphology, the current density of the hydrogen evolution increased up to two times.
Alireza Zibanejad-Rad, Ali Alizadeh, Seyyed Mehdi Abbasi,
Volume 21, Issue 2 (June 2024)
Abstract
Pressureless sintering was employed at 1400 °C to synthesize Ti matrix composites (TMCs) reinforced with in-situ TiB and TiC reinforcements using TiB2 and B4C initial reinforcements. The microstructure and wear behavior of the synthesized composites were evaluated and compared and the results showed that B4C caused the formation of TiB-TiC in-situ hybrid reinforcements in the Ti matrix. Also, TiB was in the form of blades/needles and whiskers, and TiC was almost equiaxed. Moreover, the volume fraction of the in-situ formed reinforcement using B4C was much higher than that formed using TiB2. In addition, although the hardness of the B4C-synthesized composites was higher, the composite synthesized using 3 wt.% TiB2 exhibited the highest hardness (425 HV). The wear test results showed that the sample synthesized using 3 wt.% TiB2 showed the lowest wear rate at 50 N, mainly because of its higher hardness. The dominant wear mechanism in the samples synthesized using 3 wt.% B4C was abrasive and delamination at 50 N and 100 N, respectively while in the samples synthesized 3 wt.% TiB2, a combination of delamination and adhesive wear and adhesive wear was ruling, respectively.
Ahad Saeidi, Sara Banijamali, Mojgan Heydari,
Volume 21, Issue 2 (June 2024)
Abstract
This study explores the fabrication, structural analysis, and cytocompatibility of cobalt-doped bioactive glass scaffolds for potential applications in bone tissue engineering. A specific glass composition modified from Hench's original formulation was melted, quenched, and ground to an average particle size of 10 μm. The resulting amorphous powder underwent controlled sintering to form green bodies and was extensively characterized using simultaneous differential thermal analysis (DTA), Raman spectroscopy, and Fourier Transform Infrared analysis (FTIR). After mixing with a resin and a dispersant, the composite was used in digital light processing (DLP) 3D printing to construct scaffolds with interconnected macropores. Thermal post-treatment of 3D printed scaffolds, including debinding (Removing the binder that used for shaping) and sintering, was optimized based on thermogravimetric analysis (TG) and the microstructure was examined using FE-SEM and XRD. In vitro bioactivity was assessed by immersion in simulated body fluid (SBF), while cytocompatibility with MC3T3 cells was evaluated through SEM following a series of ethanol dehydrations. The study validates the fabrication of bioactive glass scaffolds with recognized structural and morphological properties, establishing the effects of cobalt doping on glass behavior and its implications for tissue engineering scaffolds. Results show, Low cobalt levels modify the glass network and reduce its Tg to 529 oC, while higher concentrations enhance the structure in point of its connectivity. XRD results shows all prepared glasses are amorphous nature, and DTA suggests a concentration-dependent Tg relationship. Spectroscopy indicates potential Si-O-Co bonding and effects on SiO2 polymerization. Cobalt's nucleating role promotes crystalline phases, enhancing bioactivity seen in rapid CHA layer formation in SBF, advancing the prospects for bone tissue engineering materials.
Hadi Sharifidarabad, Alireza Zakeri, Mandana Adeli,
Volume 21, Issue 3 (September 2024)
Abstract
The sensitivity of lead dioxide coating properties to the deposition conditions and electrolyte composition has allowed the preparation of coatings with different properties for different applications. In this study, the effects of electrolyte additives on the electrodeposition process were investigated using electrochemical measurements such as cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscopy. The results showed that the presence of fluoride ions significantly reduce the possibility of TiO2 formation. The addition of copper ions not only prevents lead loss at the cathode, but also leads to the formation of copper oxide on the surface at initial stages, which hinders nucleation of PbO2. The presence of sodium dodecyl sulfate (SDS) also interferes with the nucleation process as it occupies active nucleation sites. The α-PbO2 interlayer prevents copper oxidation and solves the problem of lead dioxide nucleation. Finally, it was found that the simultaneous use of all additives together with the α-PbO2 interlayer has a positive effect on the coating process.
Muddukrishnaiah Kotakonda, Sajisha V.s, Aiswarya G, Safeela Nasrin Pakkiyan, Najamol A Alungal, Mayoora Kiliyankandi K, Divya Thekke Kareth, Naheeda Ashraf Verali Parambil, Saranya Sasi Mohan, Renjini Anil Sheeba, Sarika Puthiya Veettil, Dhanish Joseph, Nishad Kakkattummal, Afsal Bin Haleem Mp, Safeera Mayyeri, Thasneem Chemban Koyilott, Nasiya Nalakath, Samuel Thavamani B, Famila Rani J, Aruna Periyasamy, Chellappa V Rajesh, Rameswari Shanmugam, Marimuthu Poornima, Tina Raju, Roshni E R, Sirajudheen Mukriyan Kallungal, Lekshmi Ms Panicker, Saranya K G, Shilpa V P,
Volume 21, Issue 3 (September 2024)
Abstract
Biogenic synthesis of papain-conjugated copper metallic Nanoparticles and their antibacterial and antifungal activities Papain metallic conjugated nanoparticles (Papain-CuNPs) were synthesised using Papain and CuSO4.5H2O. Papain-CuNPs were characterized using UV-visible spectroscopy, FT-IR, HR-TEM, XRD, FE-SEM, zeta potential, and a zeta sizer. The antibacterial activity of papain-CuNPs against human infectious microorganisms (Citrobacter spp, Pseudomonas aeruginosa and Candida albicans) was investigated. The mechanism of action of papain-CuNPs was evaluated using FE-SEM and HRTM. UV spectroscopy confirmed the plasma resonance (SPR) at 679 nm, which indicated the formation of papain-CuNPs. The FT-IR spectrum absorbance peaks at 3927, 3865, 3842, 3363, 2978, and 2900 cm-1 indicate the presence of O-H and N-H of the secondary amine, and peaks at 1643 and 1572 cm-1 represent C=O functional groups in Papain-CuNPs. EDAX analysis confirmed the presence of copper in the papain-CuNPs. The zeta potential (-42.6 mV) and zeta size (99.66 d. nm) confirmed the stability and size of the nanoparticles. XRD confirmed the crystalline nature of the papain-CuNPs. FE-SEM and HRTM showed an oval structure, and the nano particles' 16.71244–34.84793 nm. The synthesized papain-NPs showed significant antibacterial activity against clinical P. aeruginosa (15 mm). MIC 125 µg/ml) showed bactericidal activity against P. aeruginosa and the mechanism of action of Papain-NPs was confirmed using an electron microscope by observing cell damage and cell shrinking. Papain-CuNPs have significant antibacterial activity and are thus used in the treatment of P. aeruginosa infections
Ahmad Ostovari Moghaddam, Olga Zaitseva, Sergey Uporov, Rahele Fereidonnejad, Dmitry Mikhailov, Nataliya Shaburova, Evgeny Trofimov,
Volume 21, Issue 3 (September 2024)
Abstract
High entropy intermetallic compounds (HEICs) are an interesting class of materials combining the properties of multicomponent solid solutions and the ordered superlattices in a single material. In this work, microstructural and magnetic properties of (CoCuFeMnNi)Al, (CoCuFeMnNi)Zn3, (FeCoMnNiCr)3Sn2, (FeCoNiMn)3Sn2 and Cu3(InSnSbGaGe) HEICs fabricated by induction melting are studied. The magnetic properties of the HEICs was determined mainly by the nature of the magnetic momentum of the constituent elements. (CoCuFeMnNi)Al and (CoCuFeMnNi)Zn3 displayed ferromagnetic behavior at 5 K, while indicated linear dependency of magnetization vs. magnetic (i.e. paramagnetic or antiferromagnetic state) at 300 K. The magnetization of (FeCoMnNiCr)3Sn2, (FeCoNiMn)3Sn2 and Cu3(InSnSbGaGe) HEICs at 300 K exhibited a nearly linear dependency to magnetic field. Among all the investigated samples, (CoCuFeMnNi)Al exhibited the best magnetic properties with a saturation magnetization of about Ms = 6.5 emu/g and a coercivity of about Hc = 100 Oe.
