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    Study of Tehran Air Pollutants Dispersion with CMAQ Modeling System

    , M.Sc. Thesis Sharif University of Technology Hashemian Nezhad, Babak (Author) ; Arhami, Mohammad (Supervisor)
    Abstract
    Tehran air quality is facing a real crisis. Reports of pertinent organizations show air quality is deteriorating in recent years and unhealthy days are increasing. As a result, study and planning in order to change this trend and moving toward improving air quality is a necessity. On the other hand, in order to make proper decisions and choosing effective approaches considering cost-effective attribute and legal, temporal and budget restrictions, selecting the right tool is essential. Air quality models are the tools which in a cost saving manner and reasonable time can provide the required results for researchers, decision makers and legislators. An applicable model correspondent with urban... 

    Evaluating the Levels of Air Pollutants and Their Affecting Factors in Highways of Tehran

    , M.Sc. Thesis Sharif University of Technology Nayebyazdi, Mohammad (Author) ; Arhami, Mohammad (Supervisor)
    Abstract
    The concentration of air pollutants in the environment is variable according to different factors, including distances from main sources. Vehicles in streets and highways are one of the most important sources of the air pollutants. Hemmat highway is one of the most significant highways in Tehran with traffic congestion of 15000 to 18000 vehicle/hour. In this research, the concentrations of PM10 and CO were determined in different distances of Shahid Hemmat highway and the relationship diagrams of traffic and meteorology to the amount and emission of air pollutants were drawn. The concentration gradient diagrams showed exponential decay, which demonstrated that more than of 50% of air... 

    Simulation of Hydrocarbon Waste-gas Combustion in Incinerator and Pollution Control

    , M.Sc. Thesis Sharif University of Technology Modarres, Mohammad Reza (Author) ; Darbandi, Masoud (Supervisor)
    Abstract
    Emission control, especially Carbon Monoxides (CO) as one of the major by-products of combustion processes, is one of the most serious challenges in burning waste-gases with high amounts of humidity and Carbon Monoxide. We investigated an oil waste-gas incinerator serving to a bitumen production line located in Pasargad Oil Company, Shazand, Arak, Iran. The aforementioned incinerator was criticized seriously for its high CO emissions. We were requested to find a solution to reduce the undesirable CO emission from that. Following the environmental standards, there is an upper limit of 150 ppm for the CO produced by an industrial waste oil incinerator. To present an inclusive solution for such... 

    Study of Change of Thermochemical Properties of DNA bases in the Presence of Neutral, Anionic, and Radical Species

    , M.Sc. Thesis Sharif University of Technology Mottaghizadeh, Ayda (Author) ; Fattahi, Alireza (Supervisor)
    Abstract
    Since we are exposed to many air pollutants such as different gases daily, this project has attempted to investigate how these gases affect nucleobases, which are the main constituent of the DNA chain. The gases used in this study are sulfur dioxide (SO2), carbon monoxide (CO) and nitric oxide (NO). Each of these gases was studied separately along with the most stable nucleobase in the neutral, anionic and cationic states. The AT and GC base pairs were also exposed to each of these gases and changes (for exampl, the acidity, proton affinity) created in the AT and GC base pairs were examined.The most important properties studied during this project include gas-nucleobase interactions, proton... 

    Study of Carbon Monoxide Emission and Dispersion in Long Motorway Spaces: A Case Study of Tohid Tunnel

    , M.Sc. Thesis Sharif University of Technology Alizadeh Aliabadi, Hamzeh (Author) ; Vaziri, Manouchehr (Supervisor)
    Abstract
    Vehicular tunnels are very prone to excess of air pollution due to their enclosed nature. Inadequate ventilation combined with high traffic flow result in elevated concentration of vehicle-induced air pollutants, which can pose serious health hazards. This study was carried out in the longest vehicular tunnel in Tehran, locally referred to as Tohid tunnel. Traffic flow characteristics, carbon monoxide level and it's dispersion along the tunnel were investigated in this project. Data were collected in 4 days and 3 times a day, 7-8 in the morning, 11-12 and 17-18 in the evening. Measurements were conducted at fixed locations, outside the tunnel,... 

    Investigation of Performance and Improvement of the Activity of MOF-based Catalysts in CO Oxidation Reaction

    , Ph.D. Dissertation Sharif University of Technology Abbasi, Fatemeh (Author) ; Ghotbi, Cyrus (Supervisor) ; Karimi Sabet, Javad (Supervisor)
    Abstract
    Different catalysts have been proposed for CO oxidation reaction and still many researches are performed to obtain a catalyst with high activity and stability. In this study, MOFs of CuBTC, MIL-101(Cr), and NH2-MIL-101(Cr) and active metal of Pd have been selected and their performances have been investigated in CO oxidation reaction. MOFs have been synthesized by hydrothermal method. Pd loading has been performed by impregnation method in various pH and in aqeous palladium nitrate solution and palladium nitrate solution in nitric acid. To reveal the effect of the nature of noble metal, activity of 1% Pt/MIL has been investigated. Amine-functionalized MIL-101(Cr) has been synthesized by... 

    Exposure Level of Vehicle Cabins to Particulate Matter and Gaseous Contaminations: Experimental Investigation and Theoretical Modeling of Influential Factors

    , M.Sc. Thesis Sharif University of Technology Saemian, Peyman (Author) ; Arhami, Mohammad (Supervisor)
    Abstract
    Mobile Sources are the main source of air pollutant emission in Tehran, the capital city of Iran. Everyday thousands of vehicles commute in roads and highways. Unfortunately, People are exposed to high level of particulate matter and gaseous contaminants in automobile cabins. Even though this environment is exposed to high pollutant concentration emitted by on-road vehicle, In comparison with other built environment, in-cabin commuter exposure and its key parameters has never been quantified. In general, this work entails measurement of in-cabin air quality, predicting mathematical models for calculating Air-Exchange-Rate (AER) in vehicles and on-road vehicle emission measurement. Our... 

    Analysis of CO Distribution in Large Tunnel Fires

    , M.Sc. Thesis Sharif University of Technology Sojoudi, Atta (Author) ; Farhanieh, Bijan (Supervisor)
    Abstract
    Fire events and the related toxicants such as CO are responsible for many fatalities inthe current century. These hazardous events are more dangerous when they occur in enclosedspaces. In the present study, a theoretical relation is developed for horizontal distribution of COin a large tunnel fire. Then, developed criterion is used to study the effect of rudimentaryparameters such as Heat Release Rate (HRR) of fire and tunnel Aspect Ratio (AR) on CO andtemperature stratification. Theoretical results of various heat release rates and aspect ratios forhorizontal distribution of CO are compared with numerical results using Fire DynamicsSimulator (FDS5.5). It is found that big fires have higher... 

    Exposure Level of Vehicle Cabins to Particulate Matter and Gaseous Contaminations: Experimental Investigation and Theoretical Modeling of Influential Factors

    , M.Sc. Thesis Sharif University of Technology Delavarrafiee, Maryam (Author) ; Arhami, Mohammad (Supervisor)
    Abstract
    Mobile Sources are the main source of air pollutant emission in Tehran, the capital city of Iran. Everyday thousands of vehicles commute in roads and highways. Unfortunately, People are exposed to high level of particulate matter and gaseous contaminants in automobile cabins. Even though this environment is exposed to high pollutant concentration emitted by on-road vehicle, In comparison with other built environment, in-cabin commuter exposure and its key parameters has never been quantified.
    In general, this work entails measurement of in-cabin air quality, predicting mathematical models for calculating Air-Exchange-Rate (AER) in vehicles and on-road vehicle emission measurement. Our... 

    Strain Effect on the CO & H2 Adsorption Upon Graphene

    , M.Sc. Thesis Sharif University of Technology Bagheri, Beytolhoda (Author) ; Irajizad, Azam (Supervisor)
    Abstract
    In this thesis, adsorption of Carbon monoxide and Hydrogen on graphene, by DFT calculation has been studied. Also effect of strain on some electrical properties, such as band structure, electrical conductivity and Density of states, for pristine graphene and adsorption CO and H2 on it has been probed. This results show that with strain up to 12% on pristine graphene , we won’t have any band gap on Fermi surface and energy adsorption for Carbon monoxide on strained graphene (up 12%) increase up 400 per cent. Also for strained graphene (12%) on Carbon monoxide adsorption condition we will have energy band gap almost a few electron volt on Fermi surface. In general this results express... 

    Development of an Analytical Framework for Evaluation of Climate Change Mitigation Policies on Iran’s Energy Security

    , M.Sc. Thesis Sharif University of Technology Eshraghi, Hadi (Author) ; Maleki, Abbas (Supervisor)
    Abstract
    Climate change and energy security are key drivers for future energy policy. While energy security has been a pillar of energy policy for about a century, concern about climate change is more recent and is bound to radically change the landscape of energy policy. Policy makers are now under increasing pressure to address these twin challenges: to develop cost-effective policies that will both ensure the security of our energy system and reduce greenhouse gas emissions.
    Main Effort in this Project is to construct an integrated model of Iran’s energy system to serve as a policy analysis tool, by which policymakers are able to identify the future effects of a wide range of policies in... 

    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) Zarrinkolah, M. T ; 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... 

    Numerical investigation of nonisothermal reduction of hematite using Syngas: The shaft scale study

    , Article Modelling and Simulation in Materials Science and Engineering ; Volume 15, Issue 5 , 2007 , Pages 487-507 ; 09650393 (ISSN) Valipour, M. S ; Saboohi, Y ; Sharif University of Technology
    2007
    Abstract
    A mathematical model is developed to investigate the reduction process of hematite in the reduction zone of the Midrex shaft furnace as a moving bed reactor. It is described as a counter-current moving bed cylindrical reactor in which hematite pellets are reduced by a gaseous mixture of hydrogen, water vapour, carbon dioxide and carbon monoxide, namely Syngas. It is laterally injected into the bed at the lower part close to the bottom. Governing equations, including continuity, momentum, energy and mass equations, are derived based on the conceptual model for both gas and solid phases in the cylindrical coordinate system. A three interface unreacted shrinking core model (USCM) is applied to... 

    Mathematical modeling of the reaction in an iron ore pellet using a mixture of hydrogen, water vapor, carbon monoxide and carbon dioxide: An isothermal study

    , Article Advanced Powder Technology ; Volume 17, Issue 3 , 2006 , Pages 277-295 ; 09218831 (ISSN) Valipour, M. S ; Motamed Hashemi, M. Y ; Saboohi, Y ; Sharif University of Technology
    VSP BV  2006
    Abstract
    A mathematical time-dependent and isothermal model based on the grain model has been developed to simulate the kinetic and thermal behaviors of a porous iron oxide pellet undergoing chemical reactions with a mixture of hydrogen, carbon monoxide, carbon dioxide and water vapor. Its novelty consists in fact that it can deal with a multi-species reducing gas and oxide pellet. In spite of previous models in which the pure reductant was applied as reducing gas, this model can indicate an actual view of pellet reduction including the effects of reducing gas utility and reducing gas ratio. A finite volume fully implicit technique was applied for solving the governing equations. The model has been... 

    A comparative kinetic study on the oxidative coupling of methane over LSCF perovskite-type catalyst

    , Article Applied Catalysis A: General ; Volume 354, Issue 1-2 , 2009 , Pages 143-152 ; 0926860X (ISSN) Taheri, Z ; Seyed Matin, N ; Safekordi, A. A ; Nazari, K ; Pashne, S. Z ; Sharif University of Technology
    2009
    Abstract
    A gas-phase heterogeneous kinetics is described over perovskite with formula La0.6Sr0.4Co0.8Fe0.2O3-δ (LSCF) for the oxidative coupling of methane under differential conversion conditions in a microcatalytic fixed-bed reactor. The ethane (C2H6) and carbon oxides (COX) formation and methane conversion rates were obtained as a function of methane and oxygen partial pressure under experimental conditions of: 0.20 < PC H4 < 0.82 atm, 0.04 < PO2 < 0.15 atm, and 1073 < T < 1173 K. The different kinetic models were examined and two Eley-Rideal mechanisms (a and b) were successfully performed to fit the experimental data into the theoretical relations from which two mechanisms having a first step of... 

    Evaluation of efficiency in zinc recovery from waste materials

    , Article 2006 TMS Fall Extraction and Processing Division: Sohn International Symposium, San Diego, CA, 27 August 2006 through 31 August 2006 ; Volume 1 , 2006 , Pages 445-452 ; 0873396332 (ISBN); 9780873396332 (ISBN) Taghavi, S. M ; Halali, M ; Sharif University of Technology
    2006
    Abstract
    In this report, the efficacy of different factors such as temperature of reaction, time of reaction and depth of bed are investigated in a process of recovery of zinc oxide from zinc ore concentration residues in a fluidized bed furnace. Under optimum conditions, there was more than 93.5% zinc oxide in products  

    An analysis of carbone monoxide distribution in large tunnel fires

    , Article Journal of Mechanical Science and Technology ; Vol. 28, Issue. 5 , 2014 , pp. 1917-1925 ; ISSN: 1738494X Sojoudi, A ; Afshin, H ; Farhanieh, B ; Sharif University of Technology
    Abstract
    Fire events and the related toxicants such as CO are responsible for many fatalities in the current century. These hazardous events are much more dangerous when they occur in enclosed spaces. In the present study, a theoretical relation is developed for horizontal distribution of CO in a large tunnel fire. Then, the developed criterion is used to study the effect of some rudimentary parameters such as the heat release rate (HRR) of fire and tunnel's aspect ratio (AR) on CO and temperature stratification. Theoretical results of various heat release rates and aspect ratios for horizontal distribution of CO are compared with numerical results using fire dynamics simulator (FDS5.5). It is found... 

    Effect of operation conditions on the catalytic performance of the Co/Mn/TiO2 catalyst for conversion of synthesis gas to light olefins

    , Article Scientia Iranica ; Volume 17, Issue 2 C , November , 2010 , Pages 168-176 ; 10263098 (ISSN) Shayegh, F ; Ghotbi, C ; Bozorgmehry Boozarjomehry, R ; Rashtchian, D ; Sharif University of Technology
    Abstract
    The effect of operation variables, such as the H2/CO molar feed ratio, gas hourly space velocity (GHSV), temperature, and pressure, on the catalytic performance of the Co/Mn/TiO2 catalyst prepared at the Research Institute of the Petroleum Industry (RIPI) was investigated, and optimum reactor conditions were obtained to produce the maximum amount of light olefins. The catalyst was prepared by co-precipitation of Co and Mn phases in the presence of commercial TiO2 with maximum selectivity for ethylene and propylene production. It was found that the [H2]/[CO]=2/1, space velocity (GHSV) of 1800 h-1, 280°C temperature and 4 bar pressure were optimum operating conditions for the modified catalyst... 

    Effect of model potential of adsorptive bond on the thermodynamic properties of adsorbed CO molecules on Ni(111) surface

    , Article Journal of Physical Chemistry B ; Volume 110, Issue 41 , 2006 , Pages 20435-20444 ; 15206106 (ISSN) Shamkhali, A. N ; Parsafar, G ; Sharif University of Technology
    American Chemical Society  2006
    Abstract
    The effect of anharmonicity on the adsorption of CO molecules on the Ni(111) surface has been investigated. The DFT calculations are used to obtain the effective adsorption potential of the CO molecule on the Ni(111) surface. First, using an appropriate slab model, the geometry of adsorption system corresponding to hep, fcc, bridge, and on-top sites with p(2 × 2) arrangement and coverage of 0.25 ML is optimized by the DFT calculations using a plane wave basis set and ultrasoft pseudopotentials; this gives the hep site as the most stable site with De = 185 kJ/mol, for which the equilibrium distance of CO from the surface and C-O bond length on the surface are found to be 1.31 and 1.192 Å,... 

    Modified LaCoO3 nano-perovskite catalysts for the environmental application of automotive CO oxidation

    , Article Chemical Engineering Journal ; Volume 148, Issue 2-3 , 2009 , Pages 306-311 ; 13858947 (ISSN) Seyfi, B ; Baghalha, M ; Kazemian, H ; Sharif University of Technology
    2009
    Abstract
    Modified perovskite-type oxides were synthesized through co-precipitation and conventional citrate methods. The synthesized perovskite materials had the nominal compositions of LaCoO3, LaCo0.8Cu0.2O3, La0.8Sr0.2Co0.8Cu0.2O 3, and La0.8M0.2FeO3 (where M = Ce and Sr). The catalytic activity of the perovskite samples (for low-temperature CO oxidation) was measured using a quartz reactor with an inlet gas mixture containing 97% N2, 1% O2, and 2% CO. The prepared perovskite samples were characterized by SEM, nitrogen adsorption (BET), XRF, and XRD analyses. The perovskite catalysts showed good structural and chemical stability up to 600 °C and high activity for the catalytic CO oxidation...