Loading...
Search for:
carbon
0.012 seconds
Total 2070 records
The effect of bainite volume fraction on wear behavior of aisi 4340 ferrite–bainite dual-phase steel
, Article Journal of Materials Engineering and Performance ; Volume 31, Issue 11 , 2022 , Pages 8687-8698 ; 10599495 (ISSN) ; Ekrami, A ; Sharif University of Technology
Springer
2022
Abstract
The tribological behaviors of an AISI 4340 ferritic-bainitic dual-phase steel with different bainite (VB) content were investigated. The effects of VB on wear resistance and the corresponding wear mechanisms were investigated using a pin-on-disk wear testing machine, at normal loads of 10 and 50 N, at a constant sliding velocity. The tensile and hardness tests showed that the yield strength, ultimate tensile strength, and hardness increased with increasing the VB. The wear test results at the 10 N normal load showed a direct correlation between the tensile and tribological behavior of the samples. Nevertheless, at the normal load of 50 N, unexpected behavior was observed due to the carbon...
Application of an amino-functionalized MIL-53(Al) MOF as an efficient, selective, and durable adsorbent for SO2removal
, Article Journal of Environmental Chemical Engineering ; Volume 10, Issue 6 , 2022 ; 22133437 (ISSN) ; Fotovat, F ; Hamzehlouyan, T ; Vahidi, M ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Sulfur dioxide (SO2) is one of the acidic components found in the flue gas that can harm industrial facilities and the environment. SO2 adsorption by metal-organic frameworks (MOFs) is an emerging method to effectively remove SO2 in low concentrations from the gas mixtures. In this study, amino-functionalized MIL-53(Al), i.e., NH2-MIL-53(Al), was synthesized through the solvothermal method and examined for SO2 adsorption at relatively moderate pressure and temperature (up to 2 bar, 25-80 °). According to the results of XRD, FT-IR, TGA, and DSC analysis, NH2-MIL-53(Al) demonstrated appropriate water, acid, and thermal stability. The SO2 adsorption capacity of NH2-MIL-53(Al) was 5.21 mmol.g-1...
Multifunctional Ag/AgCl/ZnTiO3 structures as highly efficient photocatalysts for the removal of nitrophenols, CO2 photoreduction, biomedical waste treatment, and bacteria inactivation
, Article Applied Catalysis A: General ; Volume 643 , 2022 ; 0926860X (ISSN) ; Ghasemi, S ; Hajiahmadi, S ; Rhimi, B ; Nejad, Z. G ; Karima, S ; Shahsavari, Z ; Wang, C ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Over the past few decades, biological hazards and organic pollution have become major environmental concerns. Photocatalysis has been found to be effective in minimizing the negative impacts of these issues in air and water. Lozenge shape Ag/AgCl/ZnTiO3 photocatalysts were fabricated by a facile two-step synthesis method, including hydrothermal and coprecipitation. The physicochemical characteristics and morphological properties of the structures were comprehensively described taking advantage of a multi-technique approach. The prepared photocatalysts offered excellent nitrophenol mineralization (>90%) after 90 min of visible light irradiation. Based on the spin-trapping ESR technique, •O2̅–...
Recent advances on dual-functional photocatalytic systems for combined removal of hazardous water pollutants and energy generation
, Article Research on Chemical Intermediates ; Volume 48, Issue 3 , 2022 , Pages 911-933 ; 09226168 (ISSN) ; Asghari Sarabi, G ; Samadi, M ; Yousefi, M ; Ebrahimi, M ; Moshfegh, A. Z ; Sharif University of Technology
Springer Science and Business Media B.V
2022
Abstract
Photocatalytic wastewater treatment and concurrent energy production or metal ions conversion to less harmful products have great potential to address both environmental and energy challenging issues, two of the most significant problems facing humankind. Many efforts have been devoted for achieving enhanced photocatalytic activity as well as optimizing reaction conditions and materials design. In this context, various strategies were applied to develop efficient dual-functional photocatalysts for environmental purification and simultaneous energy production. Concurrent photocatalytic degradation of organic pollutants and Cr(VI) reduction to less toxic Cr(III) improved the rate of both...
Performance evaluation and improvement of PC-SAFT equation of state for the asphaltene precipitation modeling during mixing with various fluid types
, Article Fluid Phase Equilibria ; Volume 554 , 2022 ; 03783812 (ISSN) ; Jamshidi, S ; Sharif University of Technology
Elsevier B.V
2022
Abstract
One of the significant problems of the upstream flow assurance community is precipitation or deposition of asphaltene that leads to affect the economics of oil production seriously. Knowledge of asphaltene onset pressure (AOP) and amount of asphaltene precipitation in the change of temperature, pressure, and composition is the essential information for preventing this problem. Recent studies have shown that thermodynamic models based on the solubility nature of asphaltenes using an equation of state (EOS) are the most effective approach to asphaltene behavior modeling. In this research, the common version of the SAFT equation, known as the Perturbed Chain form of Statistical Association...
Investigation of electrochemical parameters on cost-effective Zn/Ni-based electrocatalysts for electrochemical co2reduction reaction to syngas(H2+CO)
, Article Journal of the Electrochemical Society ; Volume 169, Issue 4 , 2022 ; 00134651 (ISSN) ; Beheshti, M ; Kakooei, S ; Sharif University of Technology
IOP Publishing Ltd
2022
Abstract
Electrochemical CO2 reduction reaction (CO2RR) has been studied in 0.1 M of KCl (pH of 6.96), NaHCO3 (pH of 8.3) and K2CO3 (pH of 11.36) cathodic solutions with various counter electrodes including graphite rod, SS316 rod and Pt mesh at different potential ranges on the Znx-Ni1-x bimetallic electrocatalysts. Among the Znx-Ni1-x electrocatalysts, the Zn-Ni electrode with a composition of 65 wt% Zn and 35 wt% Ni and cluster-like microstructure has the best performance for CO2RR by according to minimum coke formation and optimum CO and H2 faradaic efficiencies (CO FE% = 55% and H2 FE% = 45%). The cyclic voltammetry (CV) measurements and gas chromatography (GC) analysis for the CO2RR showed that...
Superhydrophobic and thermally conductive carbon black/hexagonal boron nitride@Fe3O4/cellulose composite paper for electromagnetic interference shielding
, Article Synthetic Metals ; Volume 285 , 2022 ; 03796779 (ISSN) ; Pourjavadi, A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Herein, a series of superhydrophobic thin polyacrylic resin-coated carbon black (CB)/hexagonal boron nitride (h-BN)@Fe3O4/cellulose composite papers with good flexibility, low density (~0.67 g/cm3), high electrical conductivity (~0.065 S/cm), good thermal conductivity (0.462 W.m−1. K−1), and with water contact angle (WCA) of 153° were successfully fabricated by a facile dip-coating/spraying method. The CB-BN@Fe3O4 distribution in cellulose matrix provided high electrical conductivity in the in-plane and thickness directions. The electrical conductivity in both in-plane and thickness directions increased by increasing the number of vacuum-assisted dip-coating cycles. Moreover, these...
Application of hybrid nanofluids in a novel combined photovoltaic/thermal and solar collector system
, Article Solar Energy ; Volume 239 , 2022 , Pages 102-116 ; 0038092X (ISSN) ; Salari, A ; Ma, T ; Lu, H ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Because of the low outflow temperature of the conventional photovoltaic thermal systems and lack of electrical production of the solar thermal collectors, a novel combined system is proposed to solve the two mentioned drawbacks. This novel system is achieved by connecting a photovoltaic thermal unit to a solar thermal collector in series. To increase the overall performance of this novel combined system, different hybrid nanofluids include (1) multiwall carbon nanotube-aluminum oxide (2) multiwall carbon nanotube-silicon carbide (3) graphene-aluminum oxide, and (4) graphene-silicon carbide are compared. The investigation is performed based on the three-dimensional simulation, and the...
A two step Microwave-assisted coke resistant mesoporous Ni-Co catalyst for methane steam reforming
, Article Fuel ; Volume 317 , 2022 ; 00162361 (ISSN) ; Sadrnezhaad, S. K ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Methane steam reforming (MSR) is an assuring reaction using steam to produce H2 as clean energy over a nicκel-based catalyst. We synthesized mesoporous monometallic NiMgAl2O4 and bimetallic NiCoMgAl2O4 catalysts in a two-step combustion method using a mix of fuels and powder metallurgy. BET-BJH, XRD, TGA, TPR, FESEM, and EDX-mapping characterized surface area, porosity, morphology, crystalline structure, and metal-support interaction behavior. The products exhibited strong interaction of well-structured MgAl2O4 spinel with NiO, in both specimens. The MSR evaluation tests at 750 °C under atmospheric pressure, CH4:H2O feed ratio of 1:1.2 showed the bimetallic catalyst has the highest...
Green carbon-based nanocomposite biomaterials through the lens of microscopes
, Article Emergent Materials ; Volume 5, Issue 3 , 2022 , Pages 665-671 ; 25225731 (ISSN) ; Ahmadi, S ; Rabiee, M ; Bagherzadeh, M ; Vahabi, H ; Jouyandeh, M ; Saeb, M. R ; Sharif University of Technology
Springer Nature
2022
Abstract
In this work, a green synthesis method was designed and practiced to develop bioactive and biocompatible carbon-based nanocomposites biomaterials. ZnO nanoparticles were synthesized in assistance of leaf extracts and added to a composite nanostructure composed of the reduced graphene oxide (rGO) and multi-walled carbon nanotubes (MWCNT). The resulting green nanocomposite revealed ability to make π-π interactions, hydrogen bonding, and van der Waals interactions with the doxorubicin (DOX). Then, the surface morphology of the synthesized nanocomposite was investigated, and the interrelationship between the surface morphology, relative cell viability, and drug uptake and release behavior were...
Cobalt vanadium chalcogenide microspheres decorated with dendrite-like fiber nanostructures for flexible wire-typed energy conversion and storage microdevices
, Article Nanoscale ; Volume 14, Issue 25 , 2022 , Pages 9150-9168 ; 20403364 (ISSN) ; Shahrokhian, S ; Sharif University of Technology
Royal Society of Chemistry
2022
Abstract
The increasing energy demand for next-generation portable and miniaturized electronics has drawn tremendous attention to develop microscale energy storage and conversion devices with light weight and flexible characteristics. Herein, we report the preparation of flower-like cobalt vanadium selenide/nickel copper selenide (CoVSe/NiCuSe) microspheres with three-dimensional hierarchical structure of micropore growth on copper wire for a flexible fiber microsupercapacitor (microSC) and overall water splitting. The CoV-LDH microspheres are anchored on the dendrite-like NiCu nanostructured Cu wire using a hydrothermal method (CoV-LDH/NiCu@CW). The sulfidation and selenization of CoV-LDH/NiCu was...
Photothermally heated and mesh-gridded solar-driven direct contact membrane distillation for high saline water desalination
, Article International Journal of Heat and Mass Transfer ; Volume 199 , 2022 ; 00179310 (ISSN) ; Asadollahi, M ; Mousavi, S.A ; Rajabi ghahnavieh, A ; Behzadi Sarok, M ; Khayet, M ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Photothermally heated and mesh-gridded membrane distillation (PHMD) system is proposed for desalination of high saline aqueous solutions. A triple-layered membrane, composed of a photothermal top nanofibrous layer containing polyacrylonitrile and dispersed carbon black nanoparticles and a polyvinylidene fluoride porous membrane supported on a nonwoven polyester, was prepared. A polypropylene mesh was used to hold the membrane. A 3D numerical simulation of the PHMD system was carried out by COMSOL and the appropriate length of the membrane module was determined. The effects of various operating parameters including solar radiation intensity on the permeate flux and thermal efficiency were...
Vancomycin removal using TiO2–clinoptilolite/UV in aqueous media and optimisation using response surface methodology
, Article International Journal of Environmental Analytical Chemistry ; 2022 ; 03067319 (ISSN) ; Yousefinejad, S ; Dehghani, M ; Borghei, S. M ; Javid, A. H ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
Investigations have shown the traces of antibiotics in surface water, groundwater, wastewater treatment plants, and drinking water. However, conventional wastewater treatment is not entirely effective for vancomycin degradation. Advanced oxidation is one of the most widespread methods of antibiotic degradation in aqueous media. Vancomycin was quantified by high-performance liquid chromatography. The Response Surface Methodology (RSM) based on Central Composite Design (CCD) was used to explore and optimise the effect of the independent variables on vancomycin degradation. Independent variables were as follows: pH (3–11), vancomycin concentration (15–75 mg/L), TiO2–clinoptilolite (25–125 mg in...
Efficacy of a novel bioactive glass-polymer composite for enamel remineralization following erosive challenge
, Article International Journal of Dentistry ; Volume 2022 , 2022 ; 16878728 (ISSN) ; Heidari, S ; Najafi, F ; Hajihasani, M ; Noshiri, N ; Nazari, N. F ; Sharif University of Technology
Hindawi Limited
2022
Abstract
Introduction. Dental caries is the most common cause of tooth loss. However, it can be stopped by enhancing remineralization. Fluoride and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) are among the most important remineralizing agents. Recent studies have used bioactive glass as a remineralizing agent in different forms. This study aimed to assess the efficacy of a composite paste (prepared by mixing urethane polypropylene glycol oligomer with bioactive glass powder for easier application). Materials and Methods. Enamel disks were cut out of the buccal surface of extracted sound third molars. The samples were randomly divided into 3 groups of 15 and underwent Vickers...
Pore network-scale visualization of the effect of brine composition on sweep efficiency and speed of oil recovery from carbonates using a photolithography-based calcite microfluidic model
, Article Journal of Petroleum Science and Engineering ; Volume 208 , 2022 ; 09204105 (ISSN) ; Nikbin Fashkacheh, H ; Mahani, H ; Sharif University of Technology
Elsevier B.V
2022
Abstract
A novel photolithography-based technique was developed to fabricate a quasi-2D heterogeneous calcite micromodel of representative elementary volume size. The effect of brine-chemistry on the mobilization of capillarity and heterogeneity trapped oil after high salinity water injection was evaluated by using diluted seawater, and seawater modified with calcium, sulphate, and silica nanoparticles. Preliminary brine screening was performed based on modified contact angle experiments under dynamic salinity alteration. The main findings are that the chemical composition of brine impacts both the ultimate oil recovery and its speed. The highest and fastest oil recovery was obtained with diluted...
Buckling and vibration analysis of FG-CNTRC plate subjected to thermo-mechanical load based on higher order shear deformation theory
, Article Mechanics Based Design of Structures and Machines ; Volume 50, Issue 4 , 2022 , Pages 1137-1160 ; 15397734 (ISSN) ; Karbon, M ; Eyvazian, A ; Jung, D. W ; Habibi, M ; Safarpour, M ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
In the present study, based on 12-unknown higher order shear deformation theory (HSDT), buckling and vibration analysis of FG-CNTRC rectangular plate are investigated for various types of temperature distribution and boundary conditions. Implementing Hamilton’s principle, the equations of motion are derived and solved by adopting the Navier solution for the simply supported boundary conditions and DQM method for other boundary conditions. Validation is carried out by comparing the numerical results with those obtained in the open literature. Also, a detailed parametric analysis is carried out to illuminate the influence of different system parameters such as CNT distributions, CNT volume...
The effect of cold-rolling prior to the inter-critical heat treatment on microstructure and mechanical properties of 4340 steel with ferrite – Martensite microstructure
, Article Materials Science and Engineering A ; Volume 830 , 2022 ; 09215093 (ISSN) ; Ekrami, A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
This study investigates the effect of cold rolling prior to inter-critical annealing on microstructure and mechanical properties of ferrite-martensite dual phase steel. Samples were heated to 850 °C for 1 h followed by oil quenching, then the steel sheet were cold rolled by 0%,10%,15% and 20% reduction in thickness. The inter-critical annealing treatment (750 °C, 120min) was performed to generate a ferrite-martensite microstructure. Microstructural studies showed that increasing the applied cold rolling, leading to increase in volume fraction of martensite and decrease in ferrite grain size. Mechanical properties of dual phase steel were measured by tensile, impact and hardness tests....
Low loaded MoS2/Carbon cloth as a highly efficient electrocatalyst for hydrogen evolution reaction
, Article International Journal of Hydrogen Energy ; Volume 47, Issue 3 , 2022 , Pages 1579-1588 ; 03603199 (ISSN) ; Mehdipour, H ; Moshfegh, A. Z ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Active edge sites of MoS2 nanosheets exhibit promising futures for hydrogen evolution reaction (HER), comparable with remarkable performances of highly cost platinum. However, 3D structures of MoS2 suffer from a lack of high mobility and unexposed active sites which lower the electrocatalytic activity. In this study, we show that there is a balance between increasing the active sites on the one hand and managing the charge transfer to facilitate the reaction on the other hand, and achieving this balance increases the efficiency of the electrocatalyst tremendously. For this purpose, we directly attached exfoliated MoS2 nanosheets onto carbon cloth (CC) substrate as a 3D network of conductive...
Detailed analysis of the effects of biodiesel fraction increase on the combustion stability and characteristics of a reactivity‐ controlled compression ignition diesel‐biodiesel/natural gas engine
, Article Energies ; Volume 15, Issue 3 , 2022 ; 19961073 (ISSN) ; Hosseini, V ; Sharif University of Technology
MDPI
2022
Abstract
A single‐cylinder marine diesel engine was modified to be operated in reactivity controlled compression ignition (RCCI) combustion mode. The engine fueling system was upgraded to a common rail fuel injection system. Natural gas (NG) was used as port fuel injection, and a die-sel/sunflower methyl ester biodiesel mixture was used for direct fuel injection. The fraction of bio-diesel in the direct fuel injection was changed from 0% (B0; 0% biodiesel and 100% diesel) to 5% (B5) and 20% (B20) while keeping the total energy input into the engine constant. The objective was to understand the impacts of the increased biodiesel fraction on the combustion characteristics and stability, emissions, and...
Economic feasibility of CO2 capture from oxy-fuel power plants considering enhanced oil recovery revenues
, Article Energy Procedia, 19 September 2010 through 23 September 2010 ; Volume 4 , September , 2011 , Pages 1886-1892 ; 18766102 (ISSN) ; Soltanieh, M ; Saboohia, Y ; Arab, M ; Sharif University of Technology
2011
Abstract
Considering the dramatic increase of greenhouse gases concentration in the atmosphere, especially carbon dioxide, reduction of these gases seems necessary to combat global warming. Fossil fuel power plants are one of the main sources of CO2 emission and several methods are under development to capture CO2 from power plants. In this paper, CO2 capture from a natural gas fired steam cycle power plant using oxyfuel combustion technology is studied. Oxy-fuel combustion is an interesting option since CO2 concentration in the flue gas is highly increased. The Integrated Environmental Control Model (IECM) developed by Carnegie Mellon University (USA) is used to evaluate the effect of this capture...