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Dana, N. ,
Dabiri A. ,
Najafi M.B. ,
Rahimi A. ,
Ishaghi S.M.M. ,
Shariati, L. ,
Shao M. ,
Borzacchiello A. ,
Rahimmanesh I. ,
Makvandi, P. ,
Nourmohammadi abadchi, A. ,
Darani, M.A. ,
Bahrevar m.a., ,
Hietschold m., Publication Date: 2025
Bioengineering and Translational Medicine (23806761) (2)pp. 257-264
Glioblastoma is a strong challenge in the worldwide field of central nervous system malignancies. GBM's inherent heterogeneity, along with the formation of an immunosuppressive tumor microenvironment, supports its resistance to current therapy methods. Immunotherapeutic methods have emerged as potential options in recent years. However, because of the inherent limits of traditional immunotherapeutic techniques innovative approaches are required. Advances in cut-edge techniques provide a possible route for improving effector cell effectiveness. This review gives insight into the complicated immunosuppressive pathways in GBM, with a particular emphasis on CAR T/NK-cell treatment as a potential achievement. Recognizing and addressing these concerns might open the way for more effective and focused glioblastoma therapies, providing hope for the future with the aim of improved outcomes for patients. In addition, this review presents valuable insights into the integration of nanotechnology into CAR T/NK cell therapy for enhanced efficiency of these personalized gene therapy products. © 2024 The Author(s). Bioengineering & Translational Medicine published by Wiley Periodicals LLC on behalf of American Institute of Chemical Engineers.
Ghehsareh, Z. ,
Sayah T. ,
Moharramnejad M. ,
Rahimitabar A. ,
Amini, A. ,
Shahi M. ,
Shahrestani N. ,
Ehsani, A. ,
Mansoori, H. ,
Nasr-esfahani, M. ,
Barzoki, A.S. ,
Zakeri, N. ,
Nourmohammadi abadchi, A. ,
Javadi M.H.M. ,
Tavakoli, N. ,
Kianpour, M. ,
Soleimani, M.H. Publication Date: 2025
Journal of Energy Storage (2352152X) pp. 266-291
Covalent organic frameworks (COFs), renowned for their extensive surface area, tunable porosity, and low density, are gaining prominence in the realm of electrochemical energy storage. Recent progress in fabricating high-performance electrodes derived from COFs has catalyzed novel methodologies in synthesis, linker selection, and structural design. In light of the increasing demand for sustainable and environmentally friendly energy generation, there has been a significant shift in scientific investigations towards utilizing porous substances for the purposes of storing and transforming energy through electrochemical means. In this context, significant efforts have been devoted to the preparation of the latest advancements in tailoring COF materials for different energy storage applications, offering a comprehensive exploration of their functional mechanisms and manufacturing processes. Emphasizing notable strides in supercapacitors and diverse rechargeable battery technologies, the article delves into the fundamental design strategies and their direct impact on the electrochemical efficacy of these systems. In the final segment, we address the prevailing challenges confronting COFs and propose prospective avenues to advance COF research in the burgeoning domain of emerging energy technologies. © 2025 Elsevier Ltd
Mousavi, S.M. ,
Soltanifar S. ,
Lanki, M. ,
Maimani h.r., ,
Nourmohammadi abadchi, A. ,
Feiz m.h., M.H. Publication Date: 2025
Psychology of Sport and Exercise (14690292) pp. 243-250
Objectives: The stereotype threat effect has captivated social and sports psychology researchers for over two decades. However, many questions remain unanswered. This research was designed to explore the spillover effects of stereotype threat in motor tasks. Design: A mixed model design with within-between-subjects was utilized, with soccer performance and throwing scores serving as the dependent variables. Method: Forty-two 10-year-old girls without mental or physical disabilities participated in the study and were randomly assigned into two groups: stereotype threat (ST) and nullified stereotype threat (NST). After measuring baseline performance in throwing and soccer tasks, the participants in the ST group received soccer-based stereotype induction. Afterwards, they performed 20 trials of soccer shooting. Half an hour later, the children were asked to perform 10 throws with the non-dominant hand. Results: Our results indicated that inducing soccer-based stereotypes towards girls led to underperformance in soccer, however, this negative effect did not spill over onto subsequent task (i.e., throwing) which was unrelated to the induced stereotype. Conclusions: Our finding regarding the stereotype threat spillover effect is novel and provides more insight into the range of effects of stereotype threat within the motor domain. The findings encourage the researcher to practice caution regarding the generalizability of the stereotype threat spillover effect, especially in motor tasks. © 2024 Elsevier Ltd
Publication Date: 2025
Urban Governance (26643286) (1)pp. 121-131
Considering the rapid growth of cities and the inability of urban management systems to address complex challenges, good urban governance has emerged as a comprehensive strategy to enhance efficiency and quality of life for urban residents. The need for transparent, accountable, and participatory governance in Iranian cities, particularly in Isfahan, is evident. The current study aims to identify the factors influencing the future realization of good urban governance in Isfahan. The study employs both quantitative and qualitative research approaches. A list of factors contributing to the realization of good urban governance in Isfahan was compiled using a Delphi questionnaire survey conducted among 30 experts. Subsequently, the variables were analyzed using the cross-impact analysis model in the MICMAC software. The results indicate that the mental and mindset transformation of municipal managers, disorder and lack of collaboration among governmental and state sectors, the absence of appropriate and up-to-date perspectives in urban management, a lack of synergy in financial, investment, and management domains, deficiencies in the authority of the City Council to formulate necessary legislation for city governance, inadequate proportions and uncoordinated communication among the governor, district governor, and city mayor, interventions and non-technical mandates imposed by the Ministry of the Interior and the Municipalities Organization within the administrative structure, shifting priorities of the municipality with changes in management, failure to transcend partisanship in urban management, and the underutilization of the full capacities of the city are among the most crucial factors affecting the future realization of good urban governance in Isfahan. © 2024 The Author(s)
Atashafrooz M. ,
Delouei A.A. ,
Sajjadi H. ,
Yan W.-M. ,
Behineh, E.S. ,
Hashemikamangar, S.S. ,
Ghaffarpasand o., O. ,
Nourmohammadi abadchi, A. ,
Afshari, A. ,
Drewnick, F. ,
Fesharaki, H.M. ,
Aghamir, Z.S. ,
Hosseinibalam, F. ,
Kamali, F. ,
Gallavardin, S. ,
Fachinger, J. ,
Borrmann, S. Publication Date: 2025
International Journal of Thermofluids (26662027) pp. 215-235
The main goal of this research is to examine the interacting impacts of buoyancy force, thermal radiation, nanoparticles concentration and magnetic force on thermal behaviors of mixed convection alumina-water nanofluid flow in an inclined Exhaust geometry. This geometry includes two inclined forward facing steps (FFSs) which are symmetrically located on the top and bottom walls of an inclined channel. These inclined steps are modeled in Cartesian coordinates by applying the embedded boundary method. The governing equations are numerically solved by means of the finite volume method and SIMPLE algorithm. The Rosseland approximation is adopted to calculate the radiative heat transfer term in the energy equation. Influences of Brownian motion on the effective thermal conductivity and viscosity of nanofluid is considered by applying the KKL correlation. The results are shown for various values of Grashof number (Gr = 0 − 30, 000), the Exhaust inclination angle (γ = 0° − 90°), radiation parameter (Rp = 0 − 1), Hartmann number (Ha = 0 − 200) and alumina nanoparticles concentration (ξ = 0 − 0.04). The predicted results indicate that the Gr, γ, Rp and Ha parameters have a considerable impact on the temperature distributions inside the bottom half domain of the Exhaust, whilst the influence of ξ parameter on these distributions is very small and ignorable. Furthermore, the maximum value of total heat transfer rate happens in the vertical Exhaust with highest values of Gr, Rp, Ha and ξ parameters (γ = 90°, Gr = 30, 000, Rp = 1, Ha = 200, ξ = 0.04). Comparing the numerical results of the present study with the results of other benchmark problems shows excellent agreement. © 2025
Soostani S.B. ,
Ranjbar M. ,
Memarian, A. ,
Mohammadi M. ,
Yaghini Z. ,
Hassanzadeh, F. ,
Akrami, L. ,
Behzadnezhad, N. ,
Rahmati adarmanabadi e., ,
Jafari e., E. ,
Malekpour, M. ,
Marandi, S.M. ,
Nourmohammadi abadchi, A. ,
Zarei, S. ,
Faramarzi, S. ,
Feiz m.h., M.H. ,
Abedi, A. ,
Sadeghi-aliabadi, H. ,
Lanki, M. ,
Bardia, F. Publication Date: 2025
BMC Plant Biology (14712229) (1)pp. 228-237
Chitosan, a non-toxic and biodegradable compound, enhances plant growth and secondary metabolite production, presenting innovative approaches to mitigating plant stress. Salinity, a common abiotic stress, significantly impairs plant growth and development. This study investigates the effects of chitosan on the physiological, biochemical, and gene expression responses of salt-stressed Brassica napus L. exposed to NaCl concentrations of 0, 50, 100, and 150 mM. Chitosan was applied as a foliar spray at concentrations of 0, 5 and 10 mg/L. The research focuses on gene expression changes in P5CS, PIP, and PAL genes in the roots and shoots of Brassica napus, revealing notable alterations, particularly in PIP expression under saline conditions. The study also observed enhanced PAL enzyme activity, increased chlorophyll and proline levels, and changes in iron, potassium, and nitrogen content. These findings demonstrate chitosan’s potential to improve plant resilience to salt stress. By modulating gene expression and enhancing physiological responses, chitosan presents a promising solution for enhancing plant tolerance to salinity, with valuable implications for agricultural practices. © The Author(s) 2025.
Kermani Alghorayshi S.T. ,
Bavarsad Z. ,
Imandoust M. ,
Abbasi S. ,
Abedini Soodani M.H. ,
Zahedi R. ,
Nourmohammadi abadchi, A. ,
Mohammadi hassanabadi a., A.M. ,
Mehrjuee m., ,
Taeri b., B. ,
Bahrevar m.a., Publication Date: 2025
Sustainable Energy Technologies and Assessments (22131388) pp. 1077-1081
The present study employed the Analytic Hierarchy Process (AHP), a renowned method for multi-criteria decision-making, to prioritize electrocatalysts for ammonia synthesis. This process considered the merits and demerits of both noble and non-noble metals electrocatalysts. The evaluation of seven parameters, including economic, lifetime, yield, selectivity, Faradaic efficiency (FE) and potentiometry, determines the justification of alternatives. In addition, there are seven types of electrocatalysts obtained from noble metals electrocatalysts, including Au, Pt, Ru, Rh, Pd, Ir, and Ag, as well as transition metal oxide (TMO), transition metal nitride (TMN), transition metal carbide (TMCA), transition metal chalcogenide (TMc), and other transition metal-based compounds (OTMB), and single atoms (SAs), derived from non-noble metals electrocatalysts, were considered as viable alternatives in light of the objective. According to the results of the multi-criteria evaluation, the criteria of yield, economic value, and lifetime had global weights of 0.306, 0.231, and 0.172, respectively, indicating their significance. Moreover, based on the criteria, Ru with a global weight of 0.189 and non-nobel metals SAs with a global weight of 0.214 are considered the most favored electrocatalysts for ammonia synthesis compared to both noble and non-noble electrocatalysts. The decision-making process considers economic justification (price), reaction yield, lifetime, FE, selectivity and potential as essential criteria, respectively. Ultimately, by closely considering the outcomes of individual atoms, the problems encountered by each catalyst can be effectively addressed, leading to impressive performance. © 2024 Elsevier Ltd
Amoozadeh, M. ,
Zarepour, A. ,
Khosravi, A. ,
Iravani, S. ,
Zarrabi, A. ,
Ardestani, M. ,
Asashiba, H. ,
Lanki, M. ,
Khorsandi, Z. ,
Hafezi r., R. ,
Asemi, A. ,
Nourmohammadi abadchi, A. ,
Keshavarzipour, F. ,
Vahed R. ,
Shabani, A. ,
Feiz, S.M.H. ,
Nezarat, A. ,
Adarmanabadi, E.R. ,
Sadeghi-aliabadi, H. ,
Varma, R.S. Publication Date: 2025
FlatChem (24522627) pp. 320-361
Two-dimensional MXenes and their derivatives have attracted significant attention in recent years for their potential applications in combination therapies, specifically in chemo-photothermal, chemodynamic, and photothermal/photodynamic treatments. MXenes offer distinct advantages in combination therapies due to their exceptional electrical conductivity, hydrophilicity, large surface area, tunable surface chemistry, and ability to enhance drug delivery and therapeutic efficacy through multifunctional applications. By incorporating MXenes into combination therapies, researchers have demonstrated enhanced therapeutic efficacy through synergistic mechanisms that improve drug delivery, increase localized heating, and amplify the generation of reactive oxygen species, thereby effectively targeting and eliminating cancer cells or contaminations. However, stability in biological environments remains a primary concern, as degradation can compromise their therapeutic effectiveness and safety. Ensuring biocompatibility is crucial, since the introduction of MXenes and their composites may trigger immune responses or cytotoxicity. Moreover, optimizing the synthesis of high-quality MXenes with uniform properties remains a logistical challenge, affecting reproducibility and scalability for clinical applications. By consolidating existing knowledge and identifying future directions, this review aims to advance MXene-based combination chemo-photothermal, chemodynamic, and photothermal/photodynamic therapies for cancer treatment and antibacterial applications, ultimately paving the way for innovative strategies in biomedicine and personalized medicine. © 2025 Elsevier B.V.
Nasier-Hussain M. ,
Samanje J.N. ,
Mokhtari K. ,
Nabi-Afjadi M. ,
Fathi Z. ,
Hosseini, A. ,
Bahreini E. ,
Shakour, N. ,
Afshar, H. ,
Behrouz b., ,
Yazdanmehr m., M. ,
Hoseinpoor, S. ,
Adibi, N. ,
Amini k., ,
Jalali asadabadi, S. ,
Rajabian, F. ,
Afshari, A. ,
Shakhniya, F. ,
Nourmohammadi abadchi, A. ,
Azimi, S.G. ,
Rohani, S. ,
Ghasemzadeh, M. ,
Iranshahi, M. ,
Saberi, F. ,
Ghasemi n., ,
Rezvanian, M. ,
Sadeghi-aliabadi, H. ,
Hadizadeh, F. Publication Date: 2025
BMC Gastroenterology (1471230X) (1)pp. 3508-3525
Background and aim: Helicobacter pylori (H.pylori), a gram-negative bacterial pathogen associated with an increased risk of gastric cancer. This study investigates potential factors in the incidence of gastric cancer in patients with H.pylori, including oxidative stress, inflammatory biomarkers, serum pepsinogens (PG) of I and II, and PG-I/PG-II ratio. Methods: The study comprised individuals with Helicobacter pylori (H.pylori) infection, gastric cancer patients, and healthy individuals. Biochemical parameters such as FBS (fasting blood sugar), lipid profile, and liver and kidney functional factors were evaluated using colorimetric techniques. Oxidative markers such as total oxidant status (TOS) and malondialdehyde (MDA) were quantified through colorimetric methods. IL-8, PG-II, and PG-II levels were also determined using the ELISA technique. Results: Individuals with H. pylori infection exhibited elevated levels of IL-8 (940.5 ± 249.7 vs. 603.4 ± 89.1 pg/ml, P < 0.0001) and oxidative species (5.47 ± 0.7 vs. 1.64 ± 0.7 nM, P < 0.05) compared to gastric cancer patients, who, despite having lower levels of IL-8 and oxidative species, showed higher levels of MDA. H.pylori patients exhibited significantly higher levels of PG-I (7.28 ± 2.1 vs. 2.61 ± 1.4 ng/ml, P < 0.001), PG-II (3.21 ± 1 vs. 2.6 ± 0.6 ng/ml, P < 0.001), and the PG-I/PG-II ratio (2.27 ± 1.2 vs. 1 ± 0.4, P < 0.001) compared to gastric cancer patients. The findings were substantiated using various data analysis platforms such as Gene Expression Profiling Interactive Analysis (GEPIA), UALCAN (The University of ALabama at Birmingham CANcer data analysis), cBioPortal, and TIMER (Tumor IMmune Estimation Resource). These parameters could serve as potential diagnostic biomarkers for screening and therapeutic interventions based on the cut-off values derived from ROC (receiver operating characteristic) curves for IL-8, PGI, PGII, and PGI/PGII across the three groups. Conclusions: IL-8, PGI, PGII, and PGI/PGII parameters could serve as potential diagnostic markers for the screening and treatment of gastric conditions. © The Author(s) 2024.
Nabizade M. ,
Mokhtari M. ,
Amin P.H. ,
Rezapour-Nasrabad R. ,
Ladani F.K. ,
Bakhtiari M. ,
Nouzari R. ,
Daman S. ,
Yazdanmehr m., M. ,
Trabelsi, N. ,
Jalali asadabadi, S. ,
Nematollahi, J. ,
Nourmohammadi abadchi, A. ,
Ahmad, I. Publication Date: 2025
Revista Latinoamericana de Hipertension (18564550) (3)pp. 136-142
Introduction: The aim of this study was to investigate the effect of feedback-based education on self-efficacy and treatment adherence in elderly diabetic patients after surgery. Methods: This quasi-experimental study used a pre-test and post-test design and was conducted on 80 elderly diabetic patients who visited the hospital after surgery. The participants were randomly assigned into two groups: experimental (40 participants) and control (40 participants). The experimental group received feed-back-based education regarding postoperative care and diabetes management, while the control group received standard education. Self-efficacy and treatment adherence were assessed before and after the intervention using validated scales. Results: The results showed that feedback-based education significantly increased self-efficacy in the patients (P < 0.001), and this increase in self-efficacy led to improved treatment adherence (P < 0.001). Structural equation modeling analysis revealed that self-efficacy significantly mediated the association between feed-back-based education and treatment adherence. Conclusion: The findings of this study indicate the effectiveness of feedback-based education in enhancing self-efficacy and treatment adherence in elderly diabetic patients after surgery. It can be suggested as an effective strategy for improving healthcare for this group of patients. © 2025, Venezuelan Society of Pharmacology and Clinical and Therapeutic Pharmacology. All rights reserved.
Nouzari R. ,
Mokhtari M. ,
Daman S. ,
Nabizadeh M. ,
Bakhtiari M. ,
Gashmard R. ,
Ladani F.K. ,
Damavandi M. ,
Shoja a., ,
Nourmohammadi abadchi, A. ,
Feiz m.h., M.H. Publication Date: 2025
Revista Latinoamericana de Hipertension (18564550) (1)pp. 1-8
Introduction: Post-traumatic growth (PTG) is known as a psychological phenomenon in which people experience positive changes in their lives after traumatic experiences. In cancer patients, social support can play an important role in facilitating this process. This systematic review examines the effect of social support on posttraumatic growth in patients with gastrointestinal cancer. Methods: Science Direct, Pub Med, Google Scholar, SID, MagIran databases were reviewed and electronic data were used to identify the psychosocial needs of the family on the burden of family care of heart patients. In the initial search, 68 articles were obtained, of which 38 duplicate articles were removed. Considering the inclusion and exclusion criteria, the number of articles was reduced to 30 articles. From this number, the articles related to the studied subject were screened and 20 studies were examined. In order to increase the strength of the research methodology and check the quality of the collected articles and prevent possible biases, three researchers who had a history of conducting systematic review style articles reviewed the articles in terms of title, abstract, introduction, methodology, results., discussion and supporting resources were discussed and their strengths and weaknesses were identified. Finally, 9 articles were included in the study. Results: The results showed that social support has a significant effect on resilience and resilience also significantly affects post-traumatic growth. High levels of social support predict high levels of adaptive coping and, consequently, post-traumatic growth. This study also showed that perceived stress can influence the relationship between social support and growth. The analyzes showed that 56.3% of the changes in post-traumatic growth are explained by the combination of social support and resilience. Conclusion: Perceived social support and resilience are two key factors that can contribute to post-traumatic growth in gastrointestinal cancer patients. Strengthening these two factors can have positive effects on the quality of life and mental health of these patients. Therefore, it is necessary to pay attention to the creation of support net works and programs to strengthen resilience for cancer patients so that they can better cope with the challenges caused by their disease. © 2025, Venezuelan Society of Pharmacology and Clinical and Therapeutic Pharmacology. All rights reserved.
Shakiba M. ,
Jahangiri, P. ,
Rahmani E. ,
Hosseini S.M. ,
Bigham, A. ,
Foroozandeh A. ,
Tajiki A. ,
Pourmadadi M. ,
Nasiri S. ,
Jouybar S. ,
Abdouss, M. ,
Nourmohammadi abadchi, A. ,
Bahrevar m.a., ,
Hietschold m., Publication Date: 2023
ACS Applied Polymer Materials (26376105) (7)pp. 5662-5675
A proper dressing for chronic wounds should be able to preserve moisture while absorbing the exudates and exhibit good antibacterial properties and reliable mechanical properties. Furthermore, drug delivery through a wound dressing is an added value that brings more therapeutic and regenerative functionalities. In this study, a carboxylated multiwalled carbon nanotube-curcumin hybrid composite was embedded in a polyamide 6/poly(vinyl alcohol) nanofibrous composite (PA6/PVA/CMWCNT-Cur) for controlled drug release and potential wound healing application. PA6/PVA/CMWCNT-Cur nanofibrous composites were synthesized in two steps. First, Cur was loaded throughout the CMWCNT, and then a cross-linked PA6/PVA/CMWCNT-Cur blend solution was electrospun at CMWCNT-Cur concentrations of 0.5, 0.75, and 1 wt %. The results showed that incorporating PVA and CMWCNT-Cur into the PA6 nanofiber improved its wettability, physical properties, and biodegradability. In addition, the optical density technique demonstrated that the produced nanofibers had high antibacterial activity, which effectively inhibited the development of Staphylococcus aureus and Escherichia coli bacteria. Due to its uniform nanofibrous structure, superior mechanical capabilities, and excellent antibacterial features, the PA6/PVA/CMWCNT-Cur hybrid nanofibrous composite containing 0.75 wt % CMWCNT-Cur was chosen as the most suitable sample. Studies on the release of Cur from the nanofibers at different pH values demonstrated a faster rate in mild acidic media. The cell viability against the L929 cell line showed that the PA6/PVA/CMWCNT-Cur hybrid nanofibrous composite significantly increased the cell viability and proliferation. This work provides a simple and quick strategy for producing a multifunctional nanofibrous mat for wound healing applications. © 2023 American Chemical Society.
Publication Date: 2021
Ceramics International (02728842) 47(21)pp. 29977-29987
The goal of this research is to fabricate pure transparent yttria ceramics through gel casting and vacuum sintering. A specific processing method has been used and optimized for this purpose. A pure yttria nanopowder was synthesized as the starting material to produce pure transparent ceramics through a low-temperature sintering process. It was attempted to minimize the undesirable nanopowder hydration by using the as-synthesized yttria nanopowder and a rapid deagglomeration and slurry preparation process. The synthesized nanopowders were deagglomerated to enhance the efficiency of both powder shaping and sintering stages. Carrageenan was used as the gelling agent because it is a low-cost and abundant material, and because the temperature is the only catalyst needed for its gelation; therefore, it is possible to control its gelation to obtain high-density and pure optical ceramics. The effect of the deagglomeration method and the processing parameters, including the amounts of dispersant, gelling agent, solid loading, pH, and deagglomeration time, on the rheology of slurry, density, and microstructure of the obtained green yttria ceramics was examined and optimized in order to obtain high solid loading nanoyttria suspensions of 38 vol%, which is more than those obtained in many of the previous investigations. The precise gelling temperature and time were measured, and green gel cast ceramics with a density of 63 % of the theoretical density were produced. A rapid deagglomeration and slurry preparation method was used instead of using a conventional planetary ball-milling approach to minimize the risk of the hydrolysis of yttria nanopowder. No sintering aid was necessary, and transparent yttria ceramics with 99 % of the theoretical density were produced after vacuum-furnace sintering at 10-2 mbar and 1715 °C. © 2021 Elsevier Ltd and Techna Group S.r.l.
Publication Date: 2019
Computational Condensed Matter (23522143) 19
The electronic structure of γ-Al 2 O 3 in the presence of the Al and O defects is investigated within the density functional theory using the PBE-GGA and TB-mBJ schemes. The formation of the Al vacancy produces acceptor-like sublevels above the valence band maximum, consistent with the previous G 0 W 0 calculations. Furthermore, the formation of the oxygen vacancy generates donor-like sublevels below the conduction band minimum, which is consistent with experiment. The donor sublevels are predicted more accurately by TB-mBJ than PBE-GGA, as electron charge density is calculated to be larger at the O vacancy site by TB-mBJ within its optimized c-factor. © 2019 Elsevier B.V.
Publication Date: 2018
Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers (13474065) 57(12)
The nanocrystallization stage was performed in a reductive hydrogen atmosphere to prevent surface oxidation and improve the soft magnetic properties of the amorphous, Fe73.5Si13.5B9Nb3Cu1 alloy through annealing. Both the amorphous and nanocrystalline Fe73.5Si13.5B9Nb3Cu1 ribbons were characterized by differential scanning calorimetry, transmission electron microscopy, X-ray diffraction, alternative gradient field magnetometry, and AC susceptometry techniques. To reduce the processing cost, commercially available industrial gas sources were used at the atmospheric pressure, instead of high purity inert gas or high vacuum ambient. The surface oxidation completely stopped after using a 70% Ar-30% H2 mixture of such gases, also the period of the nanocrystallization stage decreased. Moreover, it was observed that the soft magnetic parameters of the nanocrystalline samples depend on the annealing time. Both the in-plane permeability and coercive field of the ribbons improved through nanocrystallization and the optimum annealing time was determined. © 2018 The Japan Society of Applied Physics.
Publication Date: 2016
Journal of Ceramic Processing Research (12299162) 17(4)pp. 394-400
The aim of this article is to decrease the crystallization temperature of the tetragonal perovskite PbTiO3 nanopowders below the PbTiO3 Curie temperature (~ 500 °C). At the beginning of our study, the calcination temperature was selected based on the thermal analysis of the PbTiO3 gels, came out at 680 °C. However, detailed investigation of the thermal properties of the PbTiO3 gel revealed possibility of the formation of single tetragonal perovskite phase at lower temperatures. Pb-partitioning phenomenon (section 3.2) was investigated in detail in PbTiO3 nanopowders in order to reach good crystallization below 500 °C. Both X-Ray diffraction and transmission electron microscopy investigations showed that well crystalline pure phase PbTiO3 nanopowders have been synthesized after calcination of the PbTiO3 gel at 460 °C, which is quite close to the Curie temperature of the PbTiO3 nanoparticles. To improve crystallization of the samples prepared at 460 °C, the effects of the heat treatment parameters and Pb content on gel crystallization were investigated in detail. © 2016, Hanyang University. All rights reserved.
Publication Date: 2015
IEEE Sensors Journal (1530437X) 15(11)pp. 6454-6459
Here, a generalized induction coil sensor model (more generalized than other models) has been considered at low frequencies (within 0.1-100 Hz), and the equivalent magnetic field of the coil's thermal noise and the sensor's signal-to-noise ratio (SNR) were calculated theoretically based on the dimensions and geometry of the coil winding and its core. In our suggested theoretical consideration, all involved parameters were considered and optimized without any assumption and constraint, while some authors in their latest reports, have been used some assumptions and constraints in their sensor calculations (such as holding constant the sensor's volume and aspect ratio). Our calculations indicated that the equivalent magnetic field of the thermal noise can be minimized by the coil-to-core weight ratio. Moreover, it was found that the sensor's SNR can be maximized with only a special value of core aspect ratio (length to diameter of core ratio). The obtained theoretical results were evaluated experimentally by fabricating a search coil magnetometer model, using the optimum parameters. The resonance frequency and the parasitic capacitance of the coil were measured. Moreover, the variations of the transfer function of the magnetometer, with respect to frequency, were studied. Thus, it was shown that, at low frequencies, our experimentally measured noise data exhibit better agreement with our suggested theoretical results with respect to the state of the art. © 2001-2012 IEEE.
Papi h., ,
Jalali asadabadi, S. ,
Nourmohammadi abadchi, A. ,
Ahmad, I. ,
Nematollahi, J. ,
Yazdanmehr m., M. Publication Date: 2015
RSC Advances (20462069) 5(68)pp. 55088-55099
The optical properties of pure γ-Al2O3 and in the presence of oxygen point defects are investigated by the density functional theory approach using the PBE-GGA and TB-mBJ-GGA schemes. The optical properties of the modeled imperfect crystal show closer agreement with the experimental results than the ideal crystal. The defects produce extra sharp bands and sub-bands, in the bandgap region. The TB-mBJ scheme provides better descriptions of the bandgaps and positions of the sub-bands compared to the experiments than the PBE-GGA scheme. The imaginary part of the dielectric function reveals that the sub-bands produced by the oxygen point defects act as trapping centers. The real part of the dielectric function and the index of refraction are also strongly affected by these defects and increase at 0 eV, decrease at 5 eV and remain constant at 80 eV with the defects. The intensities of the optical spectra are calculated by PBE-GGA to be higher than those of TB-mBJ. The higher intensities are mainly ascribed to the matrix elements of the linear momentum operator. © The Royal Society of Chemistry.
Publication Date: 2014
Journal of Management and Organization (18393527) 1601(3)pp. 8-11
The aim of this research study is to produce high quality TiO2 nanotube arrays. It is shown that sol-gel electrophoresis is a suitable one to obtain vast-area TiO2 nanotube arrays when nanoporous alumina templates are used. To fabricate TiO2 nanotube arrays, alumina templates were produced via a two-step anodizing by a homemade anodizing cell using high purity phosphoric acid as the electrolyte with aluminum and platinum as electrodes. The semiconductor behavior of these templates can also be employed when producing conducting substrates for the grown TiO2 nanotubes. Stabilized titanium sol was prepared by modified hydrolysis of the titanium precursor using acetic acid. In order to produce TiO2 nanotube arrays, the template pores were filled with the precursor sol by applying a DC electric field. Then, the filled template was heat treated to crystallize the desired TiO2 phase. Scanning electron microscopy of TiO2 nanotube arrays showed that the nanotubes have been deposited in the channels of the nanoporous alumina template. X-ray diffraction data confirmed phase structure and composition of TiO2 nanotube arrays after heat treatment. To reach pure anatase phase, the samples were heated at 320°C and 400°C for two hours. To obtain pure rutile phase, the samples were heated at 320°C and 750°C for two hours. © 2013 Materials Research Society.
Publication Date: 2014
Journal of Materials Research (08842914) 29(20)pp. 2432-2440
The aim of this research study is to produce high-quality TiO2 nanotube arrays using porous alumina templates. The templates are fabricated through anodizing bulk aluminum foils which can be utilized for the production of thick alumina templates. To produce the nanotube arrays, the alumina template pores are filled with the precursor sol by applying a DC electric field. Then, the deposited nanotubes are heat treated at 320 °C for 2 h and, subsequently, sintered for 2 h at 400 and 750 °C to obtain nanotubes with pure anatase and rutile phases, respectively, as confirmed by x-ray diffraction data. Scanning and transmission electron microscopy (SEM and TEM) investigations show that the nanotubes have been deposited in the channels of the nanoporous alumina template. Also, SEM investigations show the existence of a vast area of TiO2 nanotube arrays when we use semiconductor alumina templates. Copyright © Materials Research Society 2014.
Publication Date: 2014
Materials Research Society Symposium - Proceedings (02729172) 1587
In the current research, we have utilized sol-gel electrophoresis technique to grow PbTiO3 nanotube arrays in porous anodic alumina template channels. By using this method high quality and more condense nanotubes are obtained compared with other usual sol-gel methods. Also, the effect of the anodizing parameters on the diameter of the template pores, and effect of electrophoresis voltage on wall thickness were investigated. Copyright © 2014 Materials Research Society.
Publication Date: 2013
Ferroelectrics (15635112) 448(1)pp. 123-133
Pb-partitioning phenomenon was investigated in PbTiO3 nanopowders produced via sol-gel processing in order to achieve highly crystalline and single phase tetragonal perovskite PbTiO3 nanoparticles. The calcination conditions were selected based on the simultaneous thermal analysis of the PbTiO3 gels, including complete burn out of the contained carbon and crystallization of the desired perovskite structure. X-Ray diffraction investigations confirmed key contributions of Pb stoichiometry and the gel calcination conditions to aid in improving formation of single tetragonal phase as well as avoiding formation of toxic lead compounds. Transmission electron microscopy investigations showed that well crystallized PbTiO3 nanoparticles have been synthesized after calcination of the PbTiO3 gel. © 2013 Copyright Taylor and Francis Group, LLC.
Publication Date: 2013
Ferroelectrics (15635112) 448(1)pp. 134-144
Sol-gel electrophoresis technique has been used as a usual method merely for preparing PbTiO3 thin film and nanowires with high quality and more condense layers. In this research, initially we used this technique to grow PbTiO3 nanotubes in porous anodic alumina template channels. Firstly, templates are prepared via two-step anodizing of pure aluminum foils in phosphoric acid. Then, the templates were filled with a highly stabilized PbTiO3 sol prepared and we used titanium tetra-butoxide and lead acetate trihydrate as precursors. An electric field (DC) was applied to drive the sol into the template channels. Nanotubes were formed after the etching of the porous template with 5 wt.% caustic soda solution. The heat treatment condition was evaluated based on the simultaneous thermal analysis results of the prepared and crystallization of the tetragonal perovskite structure by the X-ray diffraction of the grown nanotubes. Scanning electron microscopy investigations showed that close-packed PbTiO3 nanotubes have been grown in the template channels. © 2013 Copyright Taylor and Francis Group, LLC.
Publication Date: 2012
Nanoscale Research Letters (1556276X) 7
γ-Al2O3 is a porous metal oxide and described as a defective spinel with some cationic vacancies. In this work, we calculate the electronic density of states and band structure for the bulk of this material. The calculations are performed within the density functional theory using the full potential augmented plan waves plus local orbital method, as embodied in the WIEN2k code. We show that the modified Becke-Johnson exchange potential, as a semilocal method, can predict the bandgap in better agreement with the experiment even compared to the accurate but much more expensive green function method. Moreover, our electronic structure analysis indicates that the character of the valence band maximum mainly originates from the p orbital of those oxygen atoms that are close to the vacancy. The charge density results show that the polarization of the oxygen electron cloud is directed toward aluminum cations, which cause Al and O atoms to be tightly connected by a strong dipole bond. © 2012 Yazanmehr et al.; licensee Springer.
In the current research, we have utilized sol-gel electrophoresis technique to grow Lead Titanate (PbTiO 3) nanotubes in porous anodic alumina template channels. The templates were prepared through two-step anodizing of pure aluminum foils in phosphoric acid. The porous templates were filled with a highly stabilized PbTiO 3 sol prepared using titanium tetra-butoxide and lead acetate trihydrate, as the Ti and Pb precursors. A DC electric field was applied to drive the sol into the template channels. Tube formation was realized after etching of the template pores with 5wt. % caustic soda solution. Sol-gel electrophoresis method has already been used for preparing PbTiO 3 thin films and nanowires, and by using it, high quality and more condenses layers than other usual sol-gel methods have been produced. But, to the best of our knowledge, this method has not been used for growth of PbTiO 3 nanotubes. The heat treatment condition was evaluated based on the simultaneous thermal analysis (STA) results of the prepared and crystallization of the tetragonal perovskite structure by the X-ray diffraction (XRD) of the grown nanotubes. Scanning electron microscopy (SEM) investigations showed that close-packed PbTiO 3 nanotubes have been grown in the template channels. © 2012 IEEE.
Publication Date: 2012
International Journal of Engineering, Transactions B: Applications (1728144X) 25(4)pp. 343-349
In the current research project, sol-gel electrophoresis technique was utilized to grow titanium dioxide (TiO2) nanotubes. A titanium sol was prepared using organometallic precursors of titanium to fill the template channels. The prepared sol was driven into nanopores of porous anodic aluminum oxide templates under the influence of a DC electric field to form nanotubes on the pore walls. Successful deposition on the template pore walls was achieved after broadening the pores through chemical etching using phosphoric acid. The simultaneous thermal analysis (STA) of the samples determined the onset temperature of the anatase TiO2 crystallization. After calcination, the phase structure of the produced nanotubes was evaluated based on the X-ray diffraction (XRD) investigations. Scanning electron microscopy and energy dispersive X-ray (SEM and EDX) studies showed that TiO2 nanotubes with uniform size and shape have been electrophoretically grown in the aluminum oxide template channels.
In the current research, we have synthesized PbTiO 3 nanopowders via a sol-gel process and investigated Pb-partitioning in the produced nanopowders. Highly stabilized PbTiO 3 sols, with various Pb/Ti ratios, were prepared through chemical modification of the organometallic precursors of titanium by acetic acid. The calcination conditions were selected based on the simultaneous thermal analysis (STA) of the PbTiO 3 gels, including complete burnout of the contained carbon and crystallization of the desired perovskite structure. X-Ray diffraction (XRD) investigation demonstrated role of Pb/Ti ratio as well as the gel calcination conditions in improving formation of the tetragonal perovskite phase PbTiO 3 nanopowders and avoiding Pb-partitioning. Transmission electron microscopy (TEM), with uniform morphology, investigations showed that well crystallized PbTiO 3 nanoparticles have been synthesized after calcination the best selected PbTiO 3 gel under the optimum heat treatment conditions. © 2012 IEEE.
Publication Date: 2012
Nanoscale Research Letters (1556276X) 7(1)pp. 1-7
The photoluminescence emission of nanoporous anodic aluminum oxide films formed in phosphoric acid is studied in order to explore their defect-based subband electronic structure. Different excitation wavelengths are used to identify most of the details of the subband states. The films are produced under different anodizing conditions to optimize their emission in the visible range. Scanning electron microscopy investigations confirm pore formation in the produced layers. Gaussian analysis of the emission data indicates that subband states change with anodizing parameters, and various point defects can be formed both in the bulk and on the surface of these nanoporous layers during anodizing. © 2012 Nourmohammadi et al.; licensee Springer.
Publication Date: 2012
Reaction Kinetics, Mechanisms and Catalysis (18785204) 107(1)pp. 79-88
We have produced zinc oxide (ZnO) photocatalyst nanostructure films by the deposition of ZnO onto indium tin oxide (ITO) glass substrates. A polyethylene glycol (PEG) aided sol-gel route using zinc acetate, 2-methoxyethanol and monoethanolamine, followed by spin coating and heat treatment, was utilized to form these photocatalyst films. The obtained interface nanostructure films were characterized with X-ray diffraction, scanning electron microscopy and UV-Vis spectroscopy. The photocatalytic activity of the films were also investigated using Direct Sky Blue 5B (C. I. Direct Blue 15) as a model organic compound under UV light irradiation. The influence of operating parameters, including the pH of the solution and the number of ZnO layers on Direct Sky Blue 5B degradation, were examined. An interesting decolorization performance was observed in the ZnO/ITO thin films produced using 2 % PEG. © 2012 Akadémiai Kiadó, Budapest, Hungary.
Publication Date: 2011
Journal of Nanoscience and Nanotechnology (discontinued) (15334899) 11(10)pp. 8689-8694
In this article, we present a sol-gel method to synthesize hybrid nanocomposite films of Zinc oxide (ZnO)/methylcellulose (MC) on microscope glass slides. The zinc/MC solutions were prepared, using different weight ratios of zinc acetate dihydrate to MC, in the presence of acetic acid. Fourier transform infrared spectroscopy (FTIR) investigation of the Zn sol/MC mixture showed coordinating interaction between zinc ions and MC. Thermal gravimetry analysis (TGA) results showed rapid decomposition of organic compounds in the composites at the temperature range of 200-450 °C. The UV-Vis spectroscopy was also utilized to identify ZnO nanoparticles in the MC matrix. The generation of ZnO nanoparticles in the MC matrix was then observed to proceed in situ through the annealing of the gel phase at 200 °C. Nanocrystalline films of ZnO/MC were subsequently obtained by the calcinations of ZnO/MC nanocomposites at 550 °C. The nanocomposite films were transparent in the visible light and showed a higher energy absorption edge compared with the bulk ZnO. Nanocrystallite sizes of ZnO particles were estimated from scanning electron microscopy (SEM) and the X-ray diffraction (XRD) investigations. Copyright © 2011 American Scientific Publishers. All rights reserved.
Publication Date: 2010
Journal of Sol-Gel Science and Technology (15734846) 53(2)pp. 342-346
Lead zirconate (PbZrO3) nanotubes have been grown using porous anodic alumina templates. Sol-gel electrophoresis technique was utilized to form the nanotubes on the pore walls. The alumina templates were prepared using various anodizing voltages and times to achieve different pore diameters and lengths. Phosphoric acid solution was employed as the anodizing electrolyte. Stabilized lead zirconate sols were prepared using lead acetate trihydrate and an alkoxide precursor of zirconium. Acetic acid was used as the modifier. The prepared sols were driven into the template channels under various electrophoretic voltages and times, and the effect of the electrophoresis parameters on the formation of nanotubes was investigated. The filled templates were dried at 100 °C and sintered at 700 °C. Scanning and transmission electron microscopy (SEM and TEM) investigations demonstrated the tubular form of the lead zirconate arrays. The SEM investigations also showed the nanotubes have been efficiently grown in the template pores. The TEM studies further confirmed the polycrystalline nature of the tubes. © Springer Science+Business Media, LLC 2009.
Publication Date: 2009
Journal of Alloys and Compounds (09258388) 473(1-2)pp. 467-472
Template-based electrophoretic deposition of perovskite lead zirconate titanate (PZT) nanotubes was achieved using anodic alumina (AA) membranes and sols, containing lead, zirconium and titanium precursors. The effect of various anodizing voltages on the size of the channels in the anodic alumina template was investigated. The prepared sol was driven into the channels under the influence of various electric fields and subsequently sintered at about 700 °C. The effects of the initial heating rates and the burn-out temperature on the phase evolution of the samples were studied and a modified firing process was employed. The effects of the electrophoretic voltage and the deposition time on the average wall thickness of the tubes were investigated. Scanning and transmission electron microscopy (SEM and TEM) revealed the efficiency of electrophoresis in the growth of lead zirconate titanate nanotubes in a close-packed array. The X-ray diffraction analyses indicated the presence of perovskite as the principal phase after a modified firing schedule. © 2008 Elsevier B.V. All rights reserved.
Publication Date: 2008
Journal of Materials Science (15734803) 43(14)pp. 4753-4759
Lead zirconate titanate (PZT) nanotubes have been grown using porous anodic alumina templates. Sol-gel electrophoretic deposition method was utilized to form the nanotubes on pore walls. The templates were prepared using various anodizing voltages to achieve different pore diameters. Phosphoric acid solution was employed as the electrolyte. Stabilized PZT sols were prepared using lead acetate trihydrate and modified precursors of zirconium and titanium with acetic acid. The filled templates were then sintered at 700 °C. Scanning electron microscopy (SEM) shows that tubular PZT arrays have been efficiently grown in the alumina templates. Transmission electron microscopy (TEM) further confirms the tubular form and polycrystalline nature of the tubes. Energy dispersive X-ray (EDX) analyses also confirm the composition of the tubes. X-ray diffraction (XRD) spectra indicate the presence of the perovskite PZT as the main phase. © 2008 Springer Science+Business Media, LLC.
Publication Date: 2008
Materials Letters (18734979) 62(19)pp. 3349-3351
Sol-gel electrophoretic deposition was utilized to grow lead zirconate titanate (PZT) nanotubes through a template-based process, using porous anodic alumina templates and an acetic acid-based PZT sol. The templates were prepared employing various anodizing voltages and times to achieve different pore diameters and lengths. The PZT sol was deposited into the template channels under the influence of a DC electric field. A single-firing process was developed to transform the dried precursor gels into the perovskite PZT phase. Scanning and transmission electron microscopy show the applicability of electrophoresis technique for the deposition of tubular PZT arrays. Electron diffraction patterns also indicate the amorphous nature of the template and polycrystalline structure of the tubes. X-ray diffraction studies indicate the perovskite structure of the grown PZT nanotubes. © 2008.
Publication Date: 2007
pp. 608-611
Lead zirconate titanate (PZT) is a solid solution system with high spontaneous polarization, dielectric permittivity and piezoelectric coefficients. In the current study, we have grown lead zirconate titanate nano tubes through the template-based synthesis process. Porous anodic alumina membranes were prepared using various anodizing voltages for the templates in a cooled anodizing cell at 1° C. Phosphoric acid solution was employed as the electrolyte. The templates were then filled with prepared PZT sols. To prepare the PZT sol, lead acetate trihydrate, zirconium (IV) butoxide and titanium (IV) butoxide were used as precursor materials. SEM and EDX investigations show that nano-sized lead zirconate titanate tubes are efficiently grown in porous anodic alumina templates. XRD investigations have also shown that the grown nanotubes have ferroelectric perovskite structure.
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