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Synergistic effect of Ni-based metal organic framework with graphene for enhanced electrochemical performance of supercapacitors
, Article Journal of Materials Science: Materials in Electronics ; Volume 30, Issue 13 , 2019 , Pages 12351-12363 ; 09574522 (ISSN) ; Sedghi, A ; Hosseini, H ; Sharif University of Technology
Springer New York LLC
2019
Abstract
Developing advanced electrode materials with metal–organic frameworks (MOFs) has increasingly attracted attentions as an effective method for improving supercapacitors performances. However, their poor conductivity has limited their use in energy applications. In this paper, an effective strategy is presented to reduce the electric resistance of MOFs by the in situ synthesis of Ni-based MOFs with graphene (Ni-MOF/graphene). The fabricated Ni-MOF/graphene composite was characterized by powder X-ray diffraction (PXRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR), Raman spectra, Brunauer–Emmett–Teller (BET) and...
The tensile performance of FRP bars embedded in concrete under elevated temperatures
, Article Construction and Building Materials ; Volume 211 , 2019 , Pages 1138-1152 ; 09500618 (ISSN) ; Vatani Oskouei, A ; Khaneghahi, M. H ; Shoaei, P ; Ozbakkaloglu, T ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
In this research, the mechanical properties of glass and carbon fiber reinforced polymer (FRP) bars with epoxy resin matrices embedded in concrete were investigated under an extensive range of elevated temperatures (i.e., 25–800 °C). Embedded FRP bars with various bar diameters were studied in order to determine bar diameter influence on the results. In addition, analysis of variance (ANOVA) was performed on the experimental results to investigate the contribution of exposure temperature and bar diameter to the tensile behavior of embedded in concrete FRP bars at elevated temperatures. The results show that the tensile strength of embedded FRP bars generally decreases with increasing...
Synthesis of BiOI/ZnFe2O4-Metal-Organic Framework and g-C3N4-Based Nanocomposites for Applications in Photocatalysis
, Article Industrial and Engineering Chemistry Research ; Volume 58, Issue 23 , 2019 , Pages 9806-9818 ; 08885885 (ISSN) ; Gholami, M. R ; Sharif University of Technology
American Chemical Society
2019
Abstract
A novel binary BiOI/ZnFe2O4 (BZ) with p-n heterojunction based on the different metal-organic framework (MOF) MIL-88B(Fe) and graphite carbon nitride (g-C3N4) as substrates has been designed. As-prepared ternary nanocomposites have been first obtained via a simple hydrothermal system and subsequently deposited onto the MOF and g-C3N4 substrates. The photoactivity of the ternary nanocomposites was evaluated by organic pollutants degradation under LED light. These characterization results indicated that BiOI as a p-type semiconductor was well deposited on the surface of ZnFe2O4 (n-type semiconductors). The p-n heterojunction photocatalyst (BZ) improved the valence band potential of ZnFe2O4 and...
A novel hybrid desiccant-based ejector cooling system for energy and carbon saving in hot and humid climates
, Article International Journal of Refrigeration ; Volume 101 , Volume 101 , 2019 , Pages 196-210 ; 01407007 (ISSN) ; Rostamzadeh, H ; Avami, A ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
Desiccant-based evaporative cooling systems are considered as an energy efficient alternative to conventional vapor compression systems in humid climates. A novel hybrid desiccant-based ejector cooling (hybrid DEC) system is here presented to utilize low grade heat. In order to evaluate the system performance under subtropical humid climates, a dynamic hourly simulation of the system is performed for a typical building in Sydney. The results indicate that the hybrid DEC system is able to provide comfort conditions in subtropical and humid climates. Hybrid DEC system has a significant higher coefficient of performance compared to the conventional vapor compression system resulting to 84%...
Photocatalytic and photoluminescence properties of ZnO/graphene quasi core-shell nanoparticles
, Article Ceramics International ; Volume 45, Issue 7 , 2019 , Pages 8945-8961 ; 02728842 (ISSN) ; Nemati, A ; Simchi, R ; Choong Un, C ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
In this paper, a combination of in-situ chemical synthesis and electrolysis methods was applied for the preparation of zinc oxide/graphene oxide quasi core-shell nanoparticles. Pure zinc oxide was also prepared using the same method at different temperatures. 100 °C was selected for synthesizing the ZnO/GO quasi core-shell (zinc oxide as a core and few layers of graphene oxide as a shell). The particle size was 15 ± 2 nm in all samples. In both processes, oxygen was the main reason for the connection between the core and the shell. XRD patterns also confirmed the formation of ZnO (with regular wurtzite structure) and ZnO/GO quasi core-shell structures. Raman spectroscopy results confirmed...
Removal of Cu 2+ , Cd 2+ and Ni 2+ ions from aqueous solution using a novel chitosan/polyvinyl alcohol adsorptive membrane
, Article Carbohydrate Polymers ; Volume 210 , 2019 , Pages 264-273 ; 01448617 (ISSN) ; Soltanieh, M ; Mousavi, S. M ; Heydarinasab, A ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
The chitosan/poly vinyl alcohol membrane was modified by addition of some amine group to the membrane structure utilizing polyethyleneimine (PEI) in order to increase ionic metals adsorbent properties of the membrane. The removal percentage of the modified membranes was compared with the pristine membrane and activated carbon as common adsorbents. The membranes were characterized by FTIR, SEM, swelling degree and porosity measurement. The removal percentage of the membrane containing 0.5 wt.% PEI was more than 60% higher than the activated carbon and more than 40% higher than the pristine membrane. The modified membrane showed excellent adsorption capacity of 112.13, 86.08, and 75.5 mg/g for...
Current scenario of the tehran municipal solid waste handling rules towards green technology
, Article International Journal of Environmental Research and Public Health ; Volume 16, Issue 6 , 2019 ; 16617827 (ISSN) ; Maleki Delarestaghi, R ; Asadi, H ; Rezania, S ; Park, J ; Abbaspour, M ; Shao, W ; Sharif University of Technology
MDPI AG
2019
Abstract
This study aims to study the waste management process and recycling of municipal waste in Tehran. Currently, Kahrizak is the defined landfill area which collects the waste generated from 22 districts of Tehran. The organic wastes undergo to the windrow composting method in order to manage the partial of the waste generated in the city. Samples from the compost pile generated in Kahrizak were examined to evaluate its fertilizer value to be used further by the farmers. The results show that the obtained compost does not reach the acceptable quality to be used further in agriculture, due to lack of homogeneity, aeration and presence of heavy metals. Overall, it has been concluded that, due to...
Behavior of polymer concrete beam/pile confined with CFRP sleeves
, Article Mechanics of Advanced Materials and Structures ; Volume 26, Issue 4 , 2019 , Pages 333-340 ; 15376494 (ISSN) ; Toufigh, V ; Saadatmanesh, H ; Ahmari, S ; Kabiri, E ; Sharif University of Technology
Taylor and Francis Inc
2019
Abstract
This research investigates the flexural behavior of a polymer concrete beam/pile encased with carbon fiber sleeve. The mechanical properties of carbon fiber sleeves in tension and cement and polymer concrete in compression were determined. Polymer concrete beams were tested in flexure to determine the bending moment capacity. Then, the test results were compared to the theoretical model results. Finally, a parametric study was conducted to determine the influence of beam/pile parameters on the capacity of the element. Based on the investigation, carbon fiber sleeve filled with polymer concrete exhibits outstanding structural performance including ductility and bending capacity
Phase and microstructural evolution of low carbon MgO-C refractories with addition of Fe-catalyzed phenolic resin
, Article Ceramics International ; Volume 45, Issue 3 , 2019 , Pages 3390-3406 ; 02728842 (ISSN) ; Bavand vandchali, M ; Nemati, A ; Golestani Fard, F ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
In the present paper, phase and microstructural characterization of low carbon MgO-C refractories with addition of Fe-catalyzed phenolic resins as binder were investigated. Initially, phenolic resin was modified using various amounts of Fe particles as catalyst originated from iron nitrate ([Fe(NO3)3·9H2O]). The MgO-C matrix compositions were prepared by using 7% of modified phenolic resin, shaped and cured at 200 °C for 24 h. The cured samples were coked in the temperature range from 800 to 1400 °C and then characterized by XRD and FE-SEM techniques. Based on attained results, in-situ graphitic carbons, particularly in carbon nanotubes (CNTs) network were gradually formed from Fe-catalyzed...
Investigating the effects of pH, surfactant and ionic strength on the stability of alumina/water nanofluids using DLVO theory
, Article Journal of Thermal Analysis and Calorimetry ; Volume 135, Issue 2 , 2019 , Pages 1185-1196 ; 13886150 (ISSN) ; Yoozbashizadeh, H ; Madaah Hosseini, H. R ; Sharif University of Technology
Springer Netherlands
2019
Abstract
Alumina nanofluids are one of the most useful nanofluids. In order to evaluate the colloidal behavior of nanoparticles in alumina/water nanofluid, the influence of effective factors such as pH, ionic strength and surfactants, was studied. Zeta potential, particle size and turbidity change of each nanofluid was investigated. According to the results for 0.05, 0.1 and 0.2 mass% nanofluid, point of zero charge was obtained at pH values of 9.5, 10.2 and 10.5, respectively. The highest nanofluid stability occurred at pH 4 and its lowest was at pH 10. The anionic surfactant had a greater effect on the stability in compared with cationic and nonionic surfactants. By increasing in ionic strength,...
Countries’ classification by environmental resilience
, Article Journal of Environmental Management ; Volume 230 , 2019 , Pages 345-354 ; 03014797 (ISSN) ; Garna, R. K ; Sharif University of Technology
Academic Press
2019
Abstract
Rapid population growth, urbanization, and industrialization affect countries’ vulnerability to future disasters. This study investigates the vulnerability of 141 countries to natural and anthropogenic hazards using six environmental indicators including air pollution, greenhouse gas (GHG) emissions, access to drinking water, access to improved sanitation, environmental risks (total death and affected people), and energy use. Results confirm that the resilience varies by the location. Furthermore, this work delineates the World countries using the environmental resilience score. The most resilient countries are located in Europe and North America and the least resilient countries are in...
Finite element and experimental method for analyzing the effects of martensite morphologies on the formability of DP steels
, Article Mechanics Based Design of Structures and Machines ; 2019 ; 15397734 (ISSN) ; Torabi, M. A ; Sareban, M ; Lashini, H ; Sadeghi, E ; Fazaeli, A ; Habibi, M ; Hashemi, R ; Sharif University of Technology
Taylor and Francis Inc
2019
Abstract
In this article, we investigated the effect of martensite morphology on the mechanical properties and formability of dual phase steels. At first, three heat treatment cycles were subjected to a low-carbon steel to produce ferrite–martensite microstructure with martensite morphology of blocky-shaped, continuous, and fibrous. Tensile tests were then carried out so as to study mechanical properties, particularly the strength and strain hardening behavior of dual phase steels. In order to study the formability of dual phase samples, Forming Limit Diagram was obtained experimentally and numerically. Experimental forming limit diagram was obtained using Nakazima forming test, while Finite Element...
Intercritical heat treatment temperature dependence of mechanical properties and corrosion resistance of dual phase steel
, Article Materials Research ; Volume 22, Issue 1 , 2019 ; 15161439 (ISSN) ; Behroozi, M ; Marashi, P ; Ranjbarnodeh, E ; Pouranvari, M ; Sharif University of Technology
Universidade Federal de Sao Carlos
2019
Abstract
This study investigated the effect of intercritical heat treatment temperature on the tensile properties, work hardening and corrosion resistance of dual phase steel. Ferrite-martensite dual phase steel with different martensite volume fractions were obtained after heat treatment at different intercritical temperatures. Microstructure, mechanical properties of steel were measured and the corrosion resistance was evaluated via polarization test. Tensile strength of the specimens increased by increasing the martensite volume fraction up to 48.2%. Further increase in martensite volume fraction led to decrease in tensile strength. Work hardening behavior analyzing showed that in DP steel with...
Synthesis of SiOC/Al2O3 nano/macro composites through PDC method; investigation of potentials as layers of a packed bed reactor membrane
, Article Ceramics International ; Volume 46, Issue 11 , 2020 , Pages 19000-19007 ; Paryab, A ; Rahmani, S ; Akbari, M ; Sarpoolaky, H ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Thanks to a wide range of pore sizes by nano/macro composites of SiOC/Al2O3, such composites can serve as different layers of the structure of Packed Bed Reactor Membranes (PBRM). In the present study, the Polymer-Derived Ceramics method (PDC) has been used to synthesize nano/macro structures. Firstly, the effect of toluene as an extra carbon source on structure and microstructure of SiOC glass-ceramics was evaluated, such that, 4% (Vol) toluene was recognized as the proper amount to facilitate the synthesis of β-SiC at 1300 °C proved by XRD, Raman spectroscopy, and HR-TEM. Moreover, the presence of micro/meso-porosities was assessed by BET and TEM, indicating the capability of SiOC to serve...
Superior chemical stability of UiO-66 metal-organic frameworks (MOFs) for selective dye adsorption
, Article Chemical Engineering Journal ; Volume 399 , 2020 ; Mohammadkhani, R ; Ahmadipouya, S ; Shokrgozar, A ; Rezakazemi, M ; Molavi, H ; Aminabhavi, T. M ; Arjmand, M ; Sharif University of Technology
Elsevier B.V
2020
Abstract
The presence of dyes as pollutants in wastewater sources from textile industries can cause significant health issues if they are not adequately treated. Dye adsorption to entrap contaminants in nanoparticle pores has created considerable attention in recent years due to the environmental concerns occurring as a result of spillage of dyes in water bodies. In efforts to understand adsorption capability UiO-66, metal-organic frameworks (MOFs) were developed and examined for the separation of four pollutant dyes containing methyl red (MR), methyl orange (MO), malachite green (MG), and methylene blue (MB), which are widely used in textile industries. The adsorbent structural stability in water,...
Development of metal matrix composites and nanocomposites via double-pressing double-sintering (dpds) method
, Article Materials Today Communications ; Volume 25 , 2020 ; Latifi, R ; Angizi, S ; Mohamadbeigi, N ; Rajabi, M ; Ghasali, E ; Orooji, Y ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Achieving high densification parameter is an essential factor for metal-based composites to represent excellent mechanical characteristics. Among various compaction methods, double-pressing double-sintering (DPDS) has gained the attraction of researchers to fabricate metal-matrix composites (MMCs) as an efficient technique over the last decade. In this process, the powder will be pre-pressed and then pre-sintered; it helps reduce work hardening and prepare the sample for better densification in the next pressing and sintering step. By employing the above-mentioned method, carbon nanotube (CNT) reinforced aluminum nanocomposites; ZrB2 reinforced copper nanocomposites; and CNT reinforced...
Finite element and experimental method for analyzing the effects of martensite morphologies on the formability of DP steels
, Article Mechanics Based Design of Structures and Machines ; Volume 48, Issue 5 , 2020 , Pages 525-541 ; Torabi, M. A ; Sareban, M ; Lashini, H ; Sadeghi, E ; Fazaeli, A ; Habibi, M ; Hashemi, R ; Sharif University of Technology
Taylor and Francis Inc
2020
Abstract
In this article, we investigated the effect of martensite morphology on the mechanical properties and formability of dual phase steels. At first, three heat treatment cycles were subjected to a low-carbon steel to produce ferrite–martensite microstructure with martensite morphology of blocky-shaped, continuous, and fibrous. Tensile tests were then carried out so as to study mechanical properties, particularly the strength and strain hardening behavior of dual phase steels. In order to study the formability of dual phase samples, Forming Limit Diagram was obtained experimentally and numerically. Experimental forming limit diagram was obtained using Nakazima forming test, while Finite Element...
Applications of ultrasonic testing and machine learning methods to predict the static & fatigue behavior of spot-welded joints
, Article Journal of Manufacturing Processes ; Volume 52 , 2020 , Pages 26-34 ; Farrahi, G. H ; Kashyzadeh, K. R ; Chizari, M ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Ultrasonic Testing (UT) is one of the well-known Non-Destructive Techniques (NDT) of spot-weld inspection in the advanced industries, especially in automotive industry. However, the relationship between the UT results and strength of the spot-welded joints subjected to various loading conditions is unknown. The main purpose of this research is to present an integrated search system as a new approach for assessment of tensile strength and fatigue behavior of the spot-welded joints. To this end, Resistance Spot Weld (RSW) specimens of three-sheets were made of different types of low carbon steel. Afterward, the ultrasonic tests were carried out and the pulse-echo data of each sample were...
Propane steam reforming on mesoporous NiO–MgO–SiO2 catalysts for syngas production: Effect of the MgO/SiO2 molar ratio
, Article International Journal of Hydrogen Energy ; Volume 45, Issue 46 , 2020 , Pages 24840-24858 ; Kazemeini, M ; Rezaei, M ; Farhadi, F ; Keshavarz, A ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
In this research, a series of NiO-xMgO-SiO2 catalysts with various MgO/SiO2 molar ratios were prepared via precipitation method followed by a hydrothermal treatment in the presence of PVP as surfactant. The synergic effect between MgO and SiO2 leading to the various characteristic and catalytic performance during propane steam reforming was investigated in detail. The results showed that 15 wt% NiO-0.5MgO–SiO2 catalyst possessed the highest catalytic activity (68.9% conversion for C3H8 at 550 °C) with a negligible amount of carbon formation after 20 h of reaction duration. This superior catalytic performance can be attributed to the enhanced basicity strength along with strong metal-support...
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 ; 2020 ; Karbon, M ; Eyvazian, A ; Jung, D. W ; Habibi, M ; Safarpour, M ; Sharif University of Technology
Taylor and Francis Inc
2020
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...