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mirzaee-valadi--farshad
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Synthesis of CuCo2O4/BiVO4composites as promise and efficient catalysts for 4-nitrophenol reduction in water: Experimental and theoretical study
, Article Journal of Environmental Chemical Engineering ; Volume 9, Issue 4 , 2021 ; 22133437 (ISSN) ; Gholami, M. R ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
This study investigates the synthesis of CuCo2O4, BiVO4, and CuCo2O4/BiVO4 nanocomposite by the solvothermal method. The Physico-chemical properties of the samples were verified through Fourier Transform Infrared (FTIR) spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Transmission Electron microscope (TEM), energy-dispersive X-ray spectroscopy (EDS), Brunauer-Emmett-Teller (BET). Evaluation of catalytic efficiency of the synthesized samples were done in promoting the 4-Nitrophenol reduction to 4-Aminophenol in the existence of high amount of sodium borohydride (NaBH4) as a reducing agent, and the progress of the catalytic reaction was monitored...
Trimetallic Co-Ni-Mn metal-organic framework as an efficient electrocatalyst for alkaline oxygen evolution reaction
, Article Journal of Electroanalytical Chemistry ; Volume 922 , 2022 ; 15726657 (ISSN) ; Hatami, H ; Mirzaee Valadi, F ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Designing efficient and inexpensive catalysts toward the oxygen evolution reaction (OER) is vital for achieving sustainable and green hydrogen fuel production through water electrolysis. Herein, we have synthesized several bi- and trimetallic metal–organic frameworks (MOFs) composed of Co, Ni, and Mn metals and benzene-1,3,5-tricarboxylic acid linker. The MOFs were prepared via a simple hydrothermal method, and their electrocatalytic performances in alkaline OER were investigated. A battery of analytical techniques was employed to characterize the as-synthesized materials, including field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM),...
MIL-88A derived CoFe-layered double hydroxides with optimized composition for the enhanced electrocatalytic oxygen evolution reaction
, Article New Journal of Chemistry ; Volume 47, Issue 11 , 2023 , Pages 5555-5563 ; 11440546 (ISSN) ; Hajilo, M ; Mirzaee Valadi, F ; Sharif University of Technology
Royal Society of Chemistry
2023
Abstract
The oxygen evolution reaction (OER) as the anodic half-reaction of water electrolysis has received growing attention due to its paramount role in the green and sustainable production of hydrogen fuel and metal-air batteries. Herein, we report the synthesis of five CoFe-layered double hydroxides (CoFe-LDHs) and their application toward the electrocatalytic OER in an alkaline medium. CoFe-LDHs were prepared via a novel hydrothermal route from the MIL-88A metal-organic framework (MOF). The Co-to-Fe ratios in the LDHs were systematically modified to tune the electrocatalytic activity in the OER. It was observed that the as-prepared Co0.39Fe0.61-LDH demonstrated a superior electrocatalytic...
Selective separation of Congo Red from a mixture of anionic and cationic dyes using magnetic-MOF: Experimental and DFT study
, Article Journal of Molecular Liquids ; Volume 318 , 2020 ; Ekramipooya, A ; Gholami, M. R ; Sharif University of Technology
Elsevier B.V
2020
Abstract
La-MOF-NH2@Fe3O4 (magnetic-MOF) was used as an efficient, ultrafast, and selective adsorbent for the separation of Congo Red (CR) with 92.02% removal after 2 min. The magnetic-MOF was identified by X-ray diffraction (XRD), thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET) surface area, Zeta Potential analysis, analysis of the magnetic hysteresis, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDS). Kinetics, isotherms, the effect of pH, thermodynamic, and selectivity of CR adsorption were investigated. The results confirmed that the adsorption kinetics complied with the pseudo-second-order model. The...
Efficient reduction of organic pollutants by novel magnetic Bi2S3/NiCo2O4 MOF- derived composite: Exprimental and DFT investigation
, Article Journal of Molecular Liquids ; Volume 367 , 2022 ; 01677322 (ISSN) ; Akbarzadeh, E ; Gholami, M. R ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Novel Bi2S3/NiCo2O4 nanocomposites (BS/NCO) with various mass ratios were prepared using NiCo-MOF as precursor. The morphology, composition and structure of the as-prepared catalysts were studied by different techniques such as FE-SEM, EDX, XRD, FT-IR, VSM and BET. The as-synthesized composite with 20 % Bi2S3 (%20 BS/NCO) demonstrated the best performance in reduction reaction of 4-nitrophenol (4-NP). The enhanced catalytic activity of %20 BS/NCO composite compared to the Bi2S3 and NiCo2O4 can be assigned to the optimized synergistic effects between the two pristine materials. Thermodynamic parameters and the activation energy of the reaction in the presence of %20 BS/NCO composite were...
NiSe2Nanoparticles supported on halloysite sheets as an efficient electrocatalyst toward alkaline oxygen evolution reaction
, Article Energy and Fuels ; Volume 36, Issue 23 , 2022 , Pages 14331-14340 ; 08870624 (ISSN) ; Hatami, H ; Mirzaee Valadi, F ; Akbarzadeh, E ; Sharif University of Technology
American Chemical Society
2022
Abstract
The oxygen evolution reaction (OER) with its sluggish kinetics has imposed a significant barrier to the sustainable and green generation of hydrogen fuel (via electrolysis of water) and the development of metal-air batteries. In this study, we report an efficient and novel OER electrocatalyst based on NiSe2nanoparticles (NPs) and the naturally abundant halloysite clay mineral. The NiSe2/halloysite nanocomposite (NiSe2/H) was prepared by a simple one-step hydrothermal route. The electrocatalytic performance of the as-synthesized nanocomposite and its components (pristine NiSe2and halloysite) toward OER in 1.0 KOH solution was examined. The NiSe2/H nanocomposite exhibited a significantly...
Preparation of new MOF-808/chitosan composite for Cr(VI) adsorption from aqueous solution: Experimental and DFT study
, Article Carbohydrate Polymers ; Volume 288 , 2022 ; 01448617 (ISSN) ; Shahsavari, S ; Akbarzadeh, E ; Gholami, M. R ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
In this study, a series of Zirconium-based MOF and chitosan composites (MOF-808/chitosan) were synthesized as efficient adsorbent for Cr(VI) ions elimination from aqueous solution. MOF-808/chitosan structure and morphology was characterized by FE-SEM, EDX, XRD, BET, zeta potential analysis, FT-IR, XPS techniques. The kinetic studies ascertained that Cr(VI) adsorption over MOF-808/chitosan followed pseudo-second-order kinetic model. The adsorption isotherms fitted the Langmuir isotherm model, implying on homogeneously adsorption of Cr(VI) on the surface of MOF-808/chitosan. According to the Langmuir model, the maximum capacity was obtained to be 320.0 mg/g at pH 5. Thermodynamic investigation...
Synthesis and Characterization of Modified Nanocomposites Using MOFs for Studying the Kinetics, Thermodynamics, and Mechanism of Removal Environmental Pollutants
, Ph.D. Dissertation Sharif University of Technology ; Gholami, Mohammad Reza (Supervisor) ; Rahman Setayesh, Shahrbanoo (Co-Supervisor)
Abstract
With the development of urbanization, industrialization, explosive population growth, and environmental degradation, the world is facing a serious challenge of water pollution. Nowadays, the water-soluble pollutant such as heavy metals and dyes brought a serious threat to the aquatic organisms and human health due to their non-degradability and carcinogenicity.With the purpose of future security and to restore ecological balance, it is essential to give much significance towards the removal of unwanted toxic contaminants from water resources. In this regard, the removal of toxic pollutants from wastewater using Metal-organic frameworks (MOFs) -based composites is considered as one of the...
Design and Construction of a Neutron Porosity Probe and Comparison of its Experimental Measurement with MCNP Simulation Results
, M.Sc. Thesis Sharif University of Technology ; SohrabPour, Mostafa (Supervisor)
Abstract
Today the hydrocarbon materials rank in the list of requirements of the modern societies. The increased growth of the human population, their industrial economic activities, transportation etc. requires sufficient supplies of our resources. Therefore, the hydrocarbon resources need to be discovered and evaluated accurately. There are different methods that are used to measure underground hydrocarbon resources such as well logging. In this method, a measuring device is lowered into a well to evaluate several parameter of the surrounding soil. Nuclear well logging is a sub category of well logging that uses nuclear rays to do this measurement. This method has different types of sondes which...
Effect of content silver and heat treatment temperature on morphological, optical, and electrical properties of ITO films by sol-gel technique
, Article Journal of Nanoparticle Research ; Volume 16, Issue 9 , September , 2014 ; ISSN: 13880764 ; Dolati, A ; Sharif University of Technology
2014
Abstract
Silver-doped indium tin oxide thin films were synthesized using sol-gel dip-coating technique. The influence of different silver-dopant contents and annealing temperature on the electrical, optical, structural, and morphological properties of the films were characterized by means of four-point probe, UV-Vis spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and X-ray photoelectron spectroscope (XPS). XRD analysis confirmed the formation of cubic bixbyte structure of In2O3with silver nanoparticles annealed at 350 °C. XPS analysis showed that divalent tin transformed to tetravalent tin through oxidization, and silver nanoparticles embedded into ITO...
Effects of tin valence on microstructure, optical, and electrical properties of ITO thin films prepared by sol–gel method
, Article Journal of Sol-Gel Science and Technology ; Volume 75, Issue 3 , September , 2015 , Pages 582-592 ; 09280707 (ISSN) ; Dolati, A ; Sharif University of Technology
Kluwer Academic Publishers
2015
Abstract
Abstract: This study aimed to understand the microstructural, optical, and electrical properties of tin-doped indium oxide (ITO) prepared with tetravalent and divalent tin salts. The influence of tin valence on the electrical, optical, structural, and morphological properties of the films were characterized by the mean of four-point probe, thermogravimetric analysis, differential thermal analysis (DTA), UV–Vis spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and X-ray photoelectron spectroscope. XRD results revealed formation of cubic bixbyite structure of In2 O3 with a small shift in major peak position toward lower angles with...
Deposition of Indium-tin-oxide on Glass By Sol-gel and Effect of Noble Dopants on the Optical and Electerical Properties of Indium-tin-oxide Thin Films
, M.Sc. Thesis Sharif University of Technology ; Dolati, Abolghasem (Supervisor)
Abstract
Thin film of Indium oxide doped with tin is used as a transparent electrode for different applications like screening panels, solar cells, touch panels and elechtrochromic tools. Trading thin films of ITO are precipitated using sputtering. However sol gel method can be simple and economic to make transparent electrodes. In this thesis first ITO sols is prepared using Indium nitrate and tin chloride with two or four capacities due to the production of transparent oxides on soda lime glass. Then the effect of tin chloride with two and four capacities is investigated on resistance and optic properties. Results show that tin chloride with four capacities in comparison with tin of two capacities...
Evaluation of the Endpoint Damage of Climate Change Due to Power Plant Emissions on the Human Health Using Life Cycle Analysis
, M.Sc. Thesis Sharif University of Technology ; Avami, Akram (Supervisor)
Abstract
Preserving and promoting the health of citizens in a society is one of the most important problems addressed in any country. The power sector discharges a huge volume of carbon dioxide which intensifies the climate change and consequent human health problems.The goal of this study is to evaluate the ultimate effect of climate change caused by power plant emissions on the human health using life cycle analysis approach for different provinces in Iran. An integrated model has been developed to evaluate the impact of climate change due to power plant emissions on the human health. This model includes the equations regarding the variations in carbon dioxide concentration in the atmosphere,...
Performance-based seismic retrof itting of steel frames by the endurance time method
, Article Earthquake Spectra ; Volume 31, Issue 1 , February , 2015 , Pages 383-402 ; 87552930 (ISSN) ; Estekanchi, H. E ; Sharif University of Technology
Earthquake Engineering Research Institute
2015
Abstract
The endurance time method (ET) is a dynamic analysis procedure in which intensifying dynamic excitations are used as the loading function. Seismic performance is evaluated over the entire range of equivalent seismic intensities of interest in each response history analysis, considerably reducing computational demand. In this paper, a general methodology for performance-based retrof itting of typical steel frames by the ET method is discussed. A baseline steel momentresisting frame is considered, and its seismic performance is evaluated by the ET method, considering viscous dampers and shear wall panels as strengthening alternatives. Each retrof itting option includes several design...
Application of Endurance Time Method in Performance-based Design
, M.Sc. Thesis Sharif University of Technology ; Esmaeilpour Estekanchi, Homayun (Supervisor)
Abstract
Endurance Time (ET) method is a dynamic analysis method in which the structure is subjected to an intensifying accelerogram and its response is recorded at different times.On the other hand a new method for designing earthquake resistant structures is Performance-Based Design (P-BD) method. P-BD is a methodology in which structural design criteria are expressed in terms of achieving a set of different performance objectives. In this research the application of ET method and target curve (which is defined based on ET method concepts) in the performance-based design has been studied.Correlating time in ET method and earthquake return period, the design,assessment and retrofitting of different...
A Historical Review on Darwin's Theories and Darwinism's Philosophical
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Hassan (Supervisor)
Abstract
This thesis reviews briefly historical backgrounds and contexts of Darwin's theory and summarizes and describes his arguments in the Origin, and studies philosophical issues around Darwinism. This thesis includes four chapters: chapter one reviews historical line from Greek thinkers to ninteenth century scientists; chapter two summarizes ideas and arguments in the Origin; chapter three discusses some philosophical issues briefly; and chapter four is devoted to some conclusion
A Deep Learning MIMO Communication System Based on Auto-encoder Design
, M.Sc. Thesis Sharif University of Technology ; Hossein Khalaj, Babak (Supervisor)
Abstract
Today, the use of deep learning algorithms in the design of communication systems has received much attention. One of these areas is the partial or total design of these systems using deep networks. The overall design of a communication system using deep networks allows for global optimization and can provide better performance in cases where classical methods have suboptimal performance without significantly increasing the computational load. In this research, a comprehensive architecture for designing communication systems based on Auto-encoder neural networks is presented. This architecture has the same functionality as classical systems, considering all parts of these systems including...
Boosting the electrocatalytic performance of FeSe2 in oxygen evolution reaction via composite formation with halloysite clay mineral
, Article Journal of Alloys and Compounds ; Volume 945 , 2023 ; 09258388 (ISSN) ; Hatami, H ; Valadi, F. M ; Akbarzadeh, E ; Sharif University of Technology
Elsevier Ltd
2023
Abstract
Developing high-performance and cheap electrocatalysts to boost the indolent kinetics of the oxygen evolution reaction (OER) is pivotal for the green and efficient production of molecular hydrogen and the advancement of metal-air batteries. Here, we report the synthesis, characterization, and OER catalytic activity of a series of novel nanocomposites comprising FeSe2 nanoparticles and the naturally abundant halloysite clay mineral. The FeSe2/halloysite nanocomposites (FeSe2/H) were prepared via a simple one-step hydrothermal route. The halloysite content of the nanocomposites was systematically varied to achieve the maximum electrocatalytic performance toward OER in 1.0 M KOH solution. It...
Analysing the Effects of Monetizing Energy Carriers Subsidy on Expenditures and Welfare Criteria of Iranian Households
, M.Sc. Thesis Sharif University of Technology ; Fatemi, Farshad (Supervisor)
Abstract
In this thesis, with a review on policy simulation and economic reform analysis literature, we design a suitable method to analyze the effects of monetizing energy carriers subsidy on welfare criteria of Iranian households. The selected method is limited general equilibrium that needs demand estimates of goods, services and energy. In firs step,based on 13 years of data on “Iranian Households’ Expenditures and Income” surveys, data are provided as a pseudo-panel. Demand equations are estimated using “Seemingly Unrelated Regressions” for panel data, and elasticities are calculated. In the next step, we evaluated the equivalent variation and equivalent gain measures in each price scenarios....
Adverse Selection in Iranian Life Insurance Market
, M.Sc. Thesis Sharif University of Technology ; Fatemi, Farshad (Supervisor)
Abstract
This thesis finds evidence for the presence of adverse selection in the Iranian life insurance market. We use a unique dataset including more than one million policyholders’ profile information alongside their chosen life insurance coverage from the largest Iranian insurance company. Our results not only find evidence in support of adverse selection in this market, but also consider the magnitude of adverse selection relatively notable. Moreover, we found that in addition to the coverage, the other dimensions of contract could be the potential source of adverse selection. Particularly, we focused on the insurance duration and the payment method (monthly, annually, all-in-advance)....