Loading...
Search for:
environmental-pollutions
0.008 seconds
Total 70 records
A catalyzed method to remove polychlorinated biphenyls from contaminated transformer oil
, Article Environmental Science and Pollution Research ; Volume 29, Issue 9 , 2022 , Pages 13253-13267 ; 09441344 (ISSN) ; Gholipour Zanjani, N ; Khorasheh, F ; Arjmand, M ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
The disposal of polychlorinated biphenyls (PCBs) as persistent organic pollutants from the environment has been normally performed by isolation from soil or water because of their biological activity and toxic potential. In the present investigation, catalytic hydrodehalogenation was used to detoxify PCBs-contaminated transformer oil. All reactions were directed on an oil containing 11.09 wt% of PCBs utilizing palladium supported on multi-walled carbon nanotubes (Pd/MWCNTs). The amount of hexa-chlorine homologues reduced considerably from 5.07% to less than 800 ppm utilizing HDC at the atmosphere of argon. Moreover, the amounts of long half-lives and bioaccumulative congener of PCB 153...
Investigation and modeling of energy consumption of tall office buildings in Iran’s ‘hot-arid’ and ‘cold’ climate conditions
, Article International Journal of Low-Carbon Technologies ; Volume 16, Issue 1 , 2021 , Pages 21-34 ; 17481317 (ISSN) ; Tabe Arjmand, J ; Mohammadi, O ; Ahmadi, M. H ; El Haj Assad, M ; Sharif University of Technology
Oxford University Press
2021
Abstract
The construction of high-rise buildings has attracted human attention at the beginning of human civilizations’ formation. Presently, making tall buildings is considered as a necessary requirement due to the succeeding reasons: the population increase, the tendency to live in urban centers, the land utilization in the most populated centers of the cities, the need to decrease the cost of horizontal development of cities and technological advances. During the last century, issues related to environmental pollution and high energy use have affected these tall buildings. So, it is crucial to apply appropriate methods and patterns in order to adjust their environmental impacts as much as...
Catalytic conversion of bio-renewable glycerol to pure hydrogen and syngas: Energy management and mitigation of environmental pollution
, Article Energy Conversion and Management ; Volume 247 , 2021 ; 01968904 (ISSN) ; Lotfi Varnoosfaderani, M ; Moghadasin, M. H ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Hydrogen and syngas, as two effective clean fuels, have a considerable stake in the global fuel market. These are dominantly produced from fossil fuels through reforming processes, which lose a large amount of energy and emit numerous amounts of CO2. Bio-renewable glycerol steam reforming is an attractive alternative to traditional reforming for reducing the dependence on hydrocarbon resources and mitigating climate change. This research aims to manage a heat-integrated reactor with three concentric cylinders, containing exothermic-side (methane tri-reforming), endothermic-side (glycerol steam reforming), and permeation-side for co-production of pure hydrogen and syngas. In this process,...
Estimation of highway capacity under environmental constraints vs. conventional traffic flow criteria: A case study of Tehran
, Article Journal of Traffic and Transportation Engineering (English Edition) ; 2021 ; 20957564 (ISSN) ; Safari, F ; Hassannayebi, E ; Sharif University of Technology
Chang'an University
2021
Abstract
In this paper, the concept of environmental capacity is developed to identify a convenient maximum traffic volume which will not reduce the life quality of residents. The presented method investigates the idea of traffic capacity under environmental constraints by calculating the maximum number of vehicles allowed on roads based on acceptable levels of air and noise pollutants. In this study, the permissible noise pollution level and permissible levels of CO and NOx pollution are considered for determining environmental capacity. Results show the significant difference between environmental capacity and functional traffic capacity, introduced by the highway capacity manual (HCM) as a...
Delafossite-alumina nanocomposite for enhanced catalytic wet peroxide oxidation of anionic pollutants
, Article Journal of Hazardous Materials ; Volume 417 , 2021 ; 03043894 (ISSN) ; Nouri, O ; Xie, Z ; Setayesh, S. R ; Wei, Z ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Mass transfer efficiency and catalytic reactivity are the two major hurdles for heterogeneous catalytic wet peroxide oxidation (CWPO) technologies. To address these issues, nanocomposite CuFeO2/Al2O3 was synthesized and assessed as a novel catalyst for enhanced adsorption and oxidation of anionic pollutants (catechol and reactive red 195 (RR195)) in waters. With a positive charge on the nanocomposite by introducing Al2O3, the adsorption of anionic pollutants was promoted. The surface complexation reaction on CuFeO2/Al2O3, which fits well to the Langmuir isotherm, has engined the mass transfer of pollutants to the nanocatalyst that demonstrated 96.46% and 99.75% removal of catechol and RR195...
Hysteresis of soil water retention and shrinkage behaviour for various salt concentrations
, Article Geotechnique Letters ; Volume 11, Issue 1 , 2021 , Pages 21-29 ; 20452543 (ISSN) ; Nasiri, H ; Sharif University of Technology
ICE Publishing
2021
Abstract
Laboratory investigation on the influence of solute concentration on the soil water-retention curve (SWRC) and volumetric behaviour of expansive soils has received much attention in recent years due to increasing environmental pollution. However, most studies only considered applying wetting or drying path with almost no attention to hydraulic hysteresis. Furthermore, these studies have focused on examining expansive soils and only marginal effort has been devoted to collapsible soils. Therefore, the main objective of this study is to systematically explore the SWRC and shrinkage characteristics of an artificially made collapsible soil at various molar concentrations. The tests were...
Energy and environmental enhancement of power generation units by means of zero-flow coolant strategy
, Article International Journal of Energy Research ; Volume 45, Issue 7 , 2021 , Pages 10064-10085 ; 0363907X (ISSN) ; Qasemian, A ; Sohani, A ; Rezaei, A ; Khodaverdian, R ; Soltani, R ; Li, L. K. B ; Doranehgard, M. H ; Sharif University of Technology
John Wiley and Sons Ltd
2021
Abstract
Warm-up period is considered as the most critical phase in the operation of any device that converts the energy of a fuel into heat, electricity, and other products, including power generation units since the system efficiency and environmental pollution levels are much worse than the normal operation in that phase. Considering this point, in this study, applying the zero-flow coolant strategy to reduce the warm-up period is suggested for power generation units and it is investigated in details. An internal combustion engine is selected as the case-study and implementation of the method to enhance the performance of that from both energy and environmental aspects are studied comprehensively....
CATNAP-Sim: A comprehensive exploration and a nonvolatile processor simulator for energy harvesting systems
, Article IEEE Design and Test ; Volume 38, Issue 2 , April , 2021 , Pages 69-77 ; 21682356 (ISSN) ; Abbasinia, M ; Paridari, A ; Ejlali, A ; Sharif University of Technology
IEEE Computer Society
2021
Abstract
This article introduces an architecture exploration tool to study and understand the tradeoffs of future processor systems using nonvolatile memory and help guide the design of the future. Energy efficiency serves as a critical factor in designing embedded systems. Furthermore, the growing dominance of energy harvesting systems (EHSs) in sensor-rich applications has eventuated an emerging trend in wearable-systems and IoT devices as an alternative to battery-powered embedded systems. In this article, researchers have presented CATNAP-Sim, a simulator for EHSs, with NVP and hybrid NVM-SRAM memory
An optimization model for the long-term energy planning based on useful energy, economic and environmental pollution reduction in residential sector: a case of Iran
, Article Journal of Building Engineering ; Volume 30 , 2020 ; Fakehi, A. H ; Vakili, A ; Moeini Aghtaie, M ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Energy developments plays a crucial role in the political power, economic growth, social development and environmental degradation of developing countries. Energy consumption in residential sector is an essential issue for providing a large variety of services that are necessary for social life tasks such as heating, cooling, and lighting. Therefore, there is a need for depiction of energy outlook and selection of appropriate strategies as the main pillars of economic and political stability in each society. The main objective of this research is to design and apply a methodology that helps decision makers for simulation, optimization and analysis of the residential sector energy system. The...
Nanoporous composites of activated carbon-metal organic frameworks for organic dye adsorption: Synthesis, adsorption mechanism and kinetics studies
, Article Journal of Industrial and Engineering Chemistry ; Volume 81 , 2020 , Pages 405-414 ; Simchi, A ; Shahriyari Far, H ; Sharif University of Technology
Korean Society of Industrial Engineering Chemistry
2020
Abstract
Activated carbon (AC) is an inert adsorbent material that has widely been used in water treatment or removing of environmental pollutants from water. In order to improve the adsorption of AC, which highly depends on its pore size and surface area, we prepared highly porous adsorbent composites of activated carbon (AC)/chromium-based MOF (MIL-101(Cr)). The composite has a high specific surface area of 2440 m2 g−1 and total pore volume of 1.27 cm3 g−1. To show the efficiency of the composite as an adsorbent, the removal kinetics of anionic dyes (Direct Red 31 and Acid Blue 92) from aqueous solutions dependent on the amount of composite, adsorption time, concentration of dye and pH is...
Roles of metal, ligand and post synthetic modification on metal organic frameworks to extend their hydrophobicity and applicability toward ultra–trace determination of priority organic pollutants
, Article Analytica Chimica Acta ; Volume 1125 , 2020 , Pages 231-246 ; Abbasi, A ; Bagheri, H ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Implementation of metal organic frameworks (MOFs) in the separation science has attracted many researchers attention. In this study, the role of metal, ligand, the reaction condition and modification on the extraction efficiency of some MOFs was investigated. Among the prevalent reported MOFs, some members of the MIL and MOF–5 families were chosen, and eleven MOF–based sorbents were prepared by changing the metal and ligand type, reaction condition, and/or functionality through post synthetic modification (PSM). MIL–101 and MIL–101–NH2 based structures were initially synthesized based on the chromium and iron salts. Also, three zinc–based structures including MOF–5, [NH2(CH3)2]2...
Fast chromium removal by Shewanella sp.: an enzymatic mechanism depending on serine protease
, Article International Journal of Environmental Science and Technology ; Volume 17, Issue 1 , April , 2020 , Pages 143-152 ; Mahmoodi, R ; Mollania, N ; Kheirabadi, M ; Sharif University of Technology
Springer
2020
Abstract
Environmental pollutions with heavy metals pose serious health and ecological risks. Sabzevar in the northeast of Iran has natural chromic mines and then chromium-polluted soils and groundwater. In the present work, the metal-tolerant bacterial strain KR2 was identified as Shewanella sp. following 16S rDNA gene sequence analysis. Bioremediation ability of isolated bacterial from agricultural soils that irrigated by groundwater, Shewanella sp., was evaluated for uptaking of chromium with varying Cr(VI) concentrations from 50 to 500 ppm in aerobic conditions (pH 7.0, 37 °C). The Shewanella sp. strain KR2 showed an obvious heavy metal tolerant in the wide range of heavy metals including: Cr6+,...
Comparative assessment of sewage sludge disposal alternatives in Mashhad: a life cycle perspective
, Article Environmental Science and Pollution Research ; Volume 27, Issue 1 , 2020 , Pages 315-333 ; Tafazzoli, S. M ; Aminian, S. T ; Avami, A ; Sharif University of Technology
Springer
2020
Abstract
Municipal wastewater treatment facilities produce a lot of sludge which is concentrated with different pollutants. The sustainable design of the sludge disposal alternatives is of crucial importance for touristic cities like Mashhad in Iran. Increasing sludge generation and its accumulation in the city and more stringent legislations highlight the challenge of sludge disposal, recently. This study compares different alternatives to reach maximum possible environmental benefits as well as the most cost-effective technologies. In this study, life cycle analysis (LCA) assesses different scenarios for disposal of sewage sludge which is aerobically treated and dewatered for two real case studies....
Optimal electronic waste combination for maximal recovery of Cu-Ni-Fe by acidithiobacillus ferrooxidans
, Article Journal of Cleaner Production ; Volume 240 , 2019 ; 09596526 (ISSN) ; Yaghmaei, S ; Mousavi, M ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
E-waste has become one of the greatest sources of environmental pollution. Bioleaching is known as a new, simple, and environmentally friendly technology for metal recovery requiring low energy input, unskilled labor operations, moderate conditions, and low costs. Acidithiobacillus ferrooxidans is a famous and puissant mesophilic bacterium applied extensively to recover metals from ores and different industrial and municipal wastes. It is necessary to identify the parameters affecting consumers E-waste recycling. Separating and recovering different types of E-waste is impossible for small recycling units. There should be a specific combination of E-waste, enabling the extraction of the...
Hexagonal core–shell SiO2[–MOYI]Cl–]Ag nanoframeworks for efficient photodegradation of the environmental pollutants and pathogenic bacteria
, Article Journal of Inorganic and Organometallic Polymers and Materials ; Volume 29, Issue 4 , 2019 , Pages 1314-1323 ; 15741443 (ISSN) ; Asgarpour, F ; Akbari, A ; Eftekhari Sis, B ; Lammel, G ; Sharif University of Technology
Springer New York LLC
2019
Abstract
Hexagonal core–shell SiO2[–MOYI]Cl–]Ag nanoframeworks were synthesized via surface modification of hexagonal silica nanoparticles prepared from perlite (EP) as a cheap and abundant raw material. The prepared samples were well characterized by X-ray diffraction powder (XRD), energy dispersive X-ray (EDX), diffuse reflectance spectroscopy (DRS), Brunauer–Emmett–Teller (BET) specific surface area analysis, fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX), and transmission electron microscopy (TEM). The XRD patterns confirmed that Ag and AgCl crystalline phases were successfully loaded on the surface. The TEM images were also implied that the...
Sizing and performance analysis of standalone hybrid photovoltaic/battery/hydrogen storage technology power generation systems based on the energy hub concept
, Article International Journal of Green Energy ; Volume 14, Issue 2 , 2017 , Pages 121-134 ; 15435075 (ISSN) ; Roshandel, R ; Hamidi, A. A ; Sharif University of Technology
Taylor and Francis Inc
2017
Abstract
In this study, the optimal sizing and performance analysis of a standalone integrated solar power system equipped with different storage scenarios to supply the power demand of a household is presented. One of the main purposes when applying solar energy resource is to face the increasing environmental pollutions resulting from fossil fuel based electricity sector. To this end, and to compare and examine two energy storage technologies (battery and hydrogen storage technology), three storage scenarios including battery only, hydrogen storage technology only and hybrid storage options are evaluated. An optimization framework based on Energy Hub concept is used to determine the optimum sizes...
Reliability improvement of power system utilizing BESS with wind farm
, Article 2015 IEEE 15th International Conference on Environment and Electrical Engineering, EEEIC 2015 - Conference Proceedings, 10 June 2015 through 13 June 2015 ; 2015 , Pages 1120-1125 ; 9781479979936 (ISBN) ; Fotuhi-Firuzabad, M ; Abbaspour, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2015
Abstract
In this paper, the effect of wind power generation on power system reliability is investigated. Furthermore, reliability improvement of power system using integrated battery energy storage system and wind farm will be evaluated. Growing demand for electrical energy, gradual diminishing of fossil fuel resources and environmental pollution due to continuous exploitation of them, have led to inevitable change of energy sources in power generation. Due to the random nature of wind speed, the power output of a wind farm is fluctuating; as a result, it does not have a proper control capability. The growing penetration of wind power generation in power system could cause various problems in...
Exergy, economic, and environmental analysis of a PEM fuel cell power system to meet electrical and thermal energy needs of residential buildings
, Article Journal of Fuel Cell Science and Technology ; Volume 9, Issue 5 , 2012 ; 1550624X (ISSN) ; Ehyaei, M. A ; Mozafari, A ; Atabi, F ; Hajidavalloo, E ; Shalbaf, S ; Sharif University of Technology
ASME
2012
Abstract
In this paper, a Polymer Electrolyte Membrane (PEM) fuel cell power system including burner, steam reformer, heat exchanger, and water heater has been considered. A PEM fuel cell system is designed to meet the electrical, domestic hot water, heating, and cooling loads of a residential building located in Tehran. Operating conditions of the system with consideration of the electricity cost has been studied. The cost includes social cost of the environmental pollutants (e.g. CO 2, CO and NO). The results show that the maximum energy needs of the building can be met by 12 fuel cell stacks with nominal capacity of 8.5 kW. Annual average electricity cost of thissystem is equal to 0.39 US$/kWh and...
Drag performance of divergent tubular-truncated cones: A shape optimization study
, Article International Journal of Environmental Science and Technology ; Volume 9, Issue 1 , 2012 , Pages 105-112 ; 17351472 (ISSN) ; Rad, M ; Sharif University of Technology
2012
Abstract
The use of more efficient energy consuming devices, which are closely associated with reduction of environmental pollution, has gained significant interest in the recent decades. The reduction of drag coefficient also improves safety and durability of environmental structures subjected to high-velocity fluid flow, and causes the noise and vibration to decrease as well. This paper describes the efficiency improvement in energy management by means of reducing drag coefficient in a practical divergent tubular- truncated cone. Extensive numerical simulations with emphasis on the shape optimization study were performed in order to find minimum drag coefficient for both laminar and turbulent flows...
Assembly of CeO 2-TiO 2 nanoparticles prepared in room temperature ionic liquid on graphene nanosheets for photocatalytic degradation of pollutants
, Article Journal of Hazardous Materials ; Volume 199-200 , 2012 , Pages 170-178 ; 03043894 (ISSN) ; Setayesh, S. R ; Habibi Yangjeh, A ; Hormozi Nezhad, M. R ; Gholami, M. R ; Sharif University of Technology
2012
Abstract
CeO 2-TiO 2 nanoparticles were prepared by the sol-gel process using 2-hydroxylethylammonium formate as room-temperature ionic liquid and calcined at different temperatures (500-700°C). CeO 2-TiO 2-graphene nanocomposites were prepared by hydrothermal reaction of graphene oxide with CeO 2-TiO 2 nanoparticles in aqueous solution of ethanol. The photocatalysts were characterized by X-ray diffraction, BET surface area, diffuse reflectance spectroscopy, scanning electron microscopy, and Fourier transformed infrared techniques. The results demonstrate that the room-temperature ionic liquid inhibits the anatase-rutile phase transformation. This effect was promoted by addition of CeO 2 to TiO 2....