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Analysis of Airborne Particulate Matter Toxicity and its Origin
, M.Sc. Thesis Sharif University of Technology ; Erhami, Mohammad (Supervisor)
Abstract
Epidemiological studies have shown a positive association between particulate matters exposure and adverse health effects. However, the insufficient knowledge about the influences of components or characteristics of these particles on their health effects and toxicity leads into inefficient control practices for reducing particulates health effects. So, relationship between particles toxicity and their emission sources and components is a valuable criterion in particle emission control strategies. Moreover, as people spend most of their time in indoor environment, investigating the main sources and components of particulate toxicity in indoor environment and finding the influence of outdoor...
Modelling and Prediction Air Polutants Level in Tehran Using Dynamic Neural Networks
, M.Sc. Thesis Sharif University of Technology ; Erhami, Mohammad (Supervisor)
Abstract
In parallel to the growing of population in Tehran metropolitan, air pollution in this city has become to a major problem. From which high concentration of pollutants have adverse effects on public health, accurate estimating and forecasting of concentrations for several days ahead, can provide the possibility to implement the management measures to reduce hazard and risks. Among the air pollution models, application of statistic models based on neural network in comparison to the traditional deterministic models are easier and less costly. In most studies, static models use a classical single MLP to predict one step ahead. For this purpose ANN models are required to estimate next value of...
Modeling Airborne Particulate Matter in Tehran by CMAQ Modeling System
, M.Sc. Thesis Sharif University of Technology ; Erhami, Mohammad (Supervisor)
Abstract
In recent years, in Tehran, air pollution became one of the major problems in this city. Among air pollutants, particle matter (PM) is very important in aspect of negative effect on environment and human health. Effective control of these particles requires correct determination of rules and adopting appropriate managing policy which are mostly very cost-consuming. Rules determination and adopting appropriate policy is very challenging in Tehran due to lack of sufficient information about concentration dispersion of such particles. The aim of this study is to recognize the factors of producing PM10 and appropriate understanding of changes of particle matter concentration of Tehran by...
Environmental and Economical Assessment of Green Building Compared with Conventional Buildings in Iran (A Case study in the city of Karaj)
, M.Sc. Thesis Sharif University of Technology ; Erhami, Mohammad (Supervisor)
Abstract
This thesis studied the definition of a green building and the elements associated with the construction of a green residential apartment in comparison with traditional buildings with respect to condition of Karaj city. The first step in green construction is preparing a guideline. For this, LEED (Leadership in Energy and Environmental Design) the most well-known code for green buildings is used and Adapted with Iran’s National Building Regulations. Creating a checklist to rate buildings is one of the most important parts of Green Building Regulations. To achieve the points, US LEED certification is analyzed in both qualitative and quantitative perspectives. A questioner is applied in...
Light Duty Vehicles' Emission Reduction Potentials in Megacities
Using New Powertrain Technologies (Case Study: Tehran)
,
M.Sc. Thesis
Sharif University of Technology
;
Erhami, M. (Mohammad)
(Supervisor)
;
Pourzahedi, H. (Hossein)
(Supervisor)
Abstract
Tehran is one of the most polluted megacities in the world, and based on different studies, vehicular sources are responsible for most of the criteria pollutant emissions in this city. The number of vehicles on the streets has been increased drastically leading to growing amount of emission and this trend is continuing. In order to reduce the amount of vehicular emission, it is vital to investigate the factors affecting vehicles emission in this city. This could help to find efficient solutions to improve the situation. Hence, a low-cost methodology to estimate the vehicular emissions is developed. In this...
Source Apportionment of Air Particulate Matter (PM2.5)in Tehran Using CMB Model
, M.Sc. Thesis Sharif University of Technology ; Erhami, Mohammad (Supervisor)
Abstract
In recent years, one of the most important air pollution in Tehran in terms of creating unhealthy air quality is particulate matter and especially PM2.5. Particulate matter in Tehran is released from various sources. Identification of components and estimating the contribution of each emission sources, helps governers to find air pollution control strategies. To find out major components of PM2.5 in Tehran, a one year sampling to collect PM2.5 was conducted from February 2014 through February 2015 in AQM station at Sharif University of Technology located west of Tehran. 24-hour integrated samples collected on a 1-in-6 day schedule on both Teflon and quartz filters. TOT analysis was done for...
The Investigation of Sanitary Wastewater Disinfection Using Ultra Violet Light Irradiation in Conjunction with (TiO2+Fe2 O3 ,TiO2,H2 O2 )
, M.Sc. Thesis Sharif University of Technology ; Moslemi, Mohammad Reza (Supervisor) ; Erhami, Mohammad (Supervisor)
Abstract
Numerous strategies have been applied to deal with the drought crisis such as reusing the effluent wastewater in irrigating crops, sports spaces, parks, health, entertainment purposes etc.Although the common treatment of sewage can eliminate almost 95% to 99% of microorganisms but this level of treatment is not enough for reusing the sewage, due to the existence of Pathogenic microorganisms. Therefore, disinfecting the wastewater effluent is one of the crucial stages of sewage’s treatment for preserving water resources or reusing it. Chlorination is the most common method of disinfecting wastewater. However, using a wastewater which is disinfected through Chlorination has Harmful effect on...
Kinetics and mechanism of diallyl sulfoxide pyrolysis; a combined theoretical and experimental study in the gas phase
, Article RSC Advances ; Volume., 4, No (108) , Nov , 2014 , pp. (62809-62816) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
2014
Abstract
A combined experimental and computational study was carried out on the gas phase pyrolysis reaction of diallylsulfoxide. Allylalcohol and Thioacrolein were detected as the major products during a unimolecular reaction. Experimental kinetic studies were carried out via a static system over the pressure of 21-55 torr and temperature of 435.2-475.1 K. Based on the experiments, the reaction is homogeneous and proceeds through a zwitterionic intermediate. Computational studies at the DFT (B3LYP) and QCISD(T) levels with 6-311++G(d,p) basis set indicated a two-step concerted pathway as the possible route. Comparison between the experimental and theoretical activation parameters for the most...
A joint experimental and theoretical study of kinetic and mechanism of rearrangement of allyl p-tolyl ether
, Article Journal of Molecular Structure: THEOCHEM ; Volume 893, Issues 1–3 , January , 2009 , Pages 73–76 ; Haqgu, M. (Mohammad) ; Talebi, A ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
2009
Abstract
A joint theoretical and experimental study of the kinetic and mechanism of the rearrangement of allyl p-tolyl ether was performed in order to study the kinetic and mechanism of the reaction. Experimental studies were performed in gas phase over a temperature range of 493.15–533.15 K. The experimental Arrhenius parameters of this reaction were measured to be Ea = 36.08 kcal mol−1, ΔS# = −7.88 cal mol−1 K−1, and Log A = 11.74, experimentally. Using GC for the mixture of the reaction with and without cyclohexene demonstrated that the reaction is clean without any radical intermediates. The experimental results show that the studied reaction is unimolecular and proceeds through a concerted...
Spectral classification and multiplicative partitioning of constant-weight sequences based on circulant matrix representation of optical orthogonal codes [electronic resource]
, Article IEEE Transactions on Information Theory ; 2010 vol. 56, no. 9 ; Salehi, Jawad A ; $item.subfieldsMap.a ; Sharif University Of TechnologyCombustible organic materials : determination and prediction of combustion properties
, Book
De Gruyter
2018
Proceedings: Third International Conference on Magnetic and Superconducting Materials (MSM '03), Monastir, Tunisia, 1-4 September 2003
, Book ; Akhavan, M.(Mohammad)
Wiley-VCH
2004
The synthesis of multiphasic ionic liquid-coated Pt/Al2O3 catalysts: the selective synchronous hydrogenation of C=C and C=O bonds and the modeling of the ionic liquid and solvent effects
, Article Catalysis Science & Technology ; Issue 2, 2014 , Oct , 2013 , pages 447-455 ; Tasviri, M. (Mahboubeh) ; Khodadadi-moghaddam, M. (Mohammad) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
2013
Abstract
Various ionic liquids (ILs) and their mixtures were coated on the Pt/Al2O3 catalyst and the resulting IL-coated catalysts were used in the synchronous hydrogenation of cyclohexene and acetone. The rate constant (k) and selectivity (S) toward CO hydrogenation were determined for several catalysts in various solvents. The solvatochromic parameters (ETN, normalized polarity parameter; π*, dipolarity-polarizability; β, hydrogen-bond acceptor basicity; α, hydrogen-bond donor acidity) were determined for the used ILs and solvents and the obtained selectivities were modeled based on the solvatochromic parameters of the IL layer and bulk solvent while using the Multiparameter Linear Regression (MLR)...
Performance analysis of slotted ALOHA random access Packet-Switching optical CDMA networks using generalized optical orthogonal codes and M-ary overlapping PPM signaling
, Article Journal of Optical Communications and Networking ; Volume 3, Issue 7, Article number 5910463 , July , 2011 , Pages 568-576 ; Khazrae, S. (Simin) ; Pakravan, M. R. (Mohammad Reza) ; Sharif University of Technology
2011
Abstract
In this paper we study slotted ALOHA random access optical code division multiple access packet-switching networks with a chip-level receiver structure. We use generalized optical orthogonal codes (GOOCs) and the overlapping pulse position modulation (OPPM) signaling technique to improve system performance. The impact of physical layer parameters such as the GOOC cross-correlation value and the OPPM overlapping index on key performance benchmarks such as network throughput and delay are analyzed. We also study the stability of the network based on the number of backlogged users, using the expected state drift. It has been shown that using GOOC instead of strict optical orthogonal codes...
Evaluating the effect of non-poisson traffic patterns on power consumption of sleep mode in the IEEE 802.16e MAC
, Article 4th IEEE and IFIP International Conference on Wireless and Optical Communications Networks, WOCN 2007, Singapore, 2 July 2007 through 4 July 2007 ; 2007 ; 1424410045 (ISBN); 9781424410040 (ISBN) ; Nayebi, M. M ; Sharif University of Technology
2007
Abstract
In this paper, we study the effect of non-Poisson traffic patterns on energy consumption for IEEE 802.16e nodes while operating in the sleep mode. In the sleep mode, a Mobile Subscribe Station (MSS) sleeps for a sleep interval and wakes up at the end of this interval in order to check buffered packet(s) at Base Station (BS) destined to it. If there is no packet, the MSS increases the sleep window up to the maximum value and sleeps again. For a more general traffic pattern (rather than Poisson), we evaluate the average power consumption. Based on our analysis, we conclude that traffic pattern plays an important role in power consumption. ©2007 IEEE
An experimental and computational study on the rate constant of electrochemically generated n-acetyl-p- quinoneimine with dimethylamine
, Article International Journal of Electrochemical Science ; Vol.3, Issue 10 , September , 2008 , PP. 1092-1107 ; 14523981 ; Haqgu, M. (Mohammad) ; Nematollahi, D. (Davood) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
2008
Abstract
Electrochemical oxidation of acetaminophen (N–acetyl–p–aminophenol) (1) has been studied in the presence of dimethylamine (2) as a nucleophile in aqueous solution, by means of cyclic voltammetry and controlled-potential coulometry. The results indicate the participation of electrochemically generated N-acetyl-p-quinoneimine (1a) in Michael reaction with dimethylamine (2). Based on ECE mechanism, the observed homogeneous rate constant (kobs) of the above mentioned reaction is estimated by comparing the experimental cyclic voltammograms with the digital simulated results. Further more; kinetics and mechanism of the reaction were studied with ab initio calculation, Monte Carlo and QM/MM...
Colloidal gold nanoparticles: an unexpected catalytic activity in aqueous phase with dioxygen
, Article catalysis letters ; Volume 144, Issue 7 , July , 2014 , pp. 1219-1222 ; 1572-879X ; Robatjazi, H. (Hossein) ; Hormozi-Nezhad, M. (Mohammad Reza) ; Padervand, M. (Mohsen) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
2014
Abstract
Selective oxidations of alkenes were investigated using molecular oxygen in aqueous solution under mild conditions. Colloidal gold nanoparticles are particularly versatile catalysts for oxidation reaction with exceptionally high efficiency and significant selectivity. Gold nanorods (Au NRs) exhibited a slightly enhanced activity compare to gold nanospheres
Mechanical and metallurgical properties of dissimilar AA6061-T6 and AA7277-T6 joint made by FSW technique
, Article International Journal of Advanced Manufacturing Technology ; Volume 86, Issue 9-12 , 2016 , Pages 2551-2565 ; 02683768 (ISSN) ; Shahheidari, M ; Bisadi, M ; Akbari, M ; Hossain, S ; Sharif University of Technology
Springer-Verlag London Ltd
2016
Abstract
Aluminum 6xxx and 7xxx series are among the most commonly used alloys in industrial applications whereas their joining and welding using conventional fusion-based weld processes are very difficult. In this paper, friction stir welding process of dissimilar AA6061-T6 and AA-7277-T6 aluminum plates was investigated. The effects of tool travers and rotational speeds and the type of material located in the advanced side (AS) or retreating side (RS) of weldment were studied experimentally on the mechanical and metallurgical characteristics of the joint. Macro- and microstructure pictures of weld region were used to evaluate the quality of the weld and defect detections. Tensile strength tests and...
An adaptive latency mitigation scheme for massively multiuser virtual environments
, Article Journal of Network and Computer Applications ; Volume 32, Issue 5 , September , 2009 , Pages 1049–1063 ; Shirmohammadi, Sh. (Shervin) ; Pakravan, M. R. (Mohammad Reza) ; Alavi, M. R. (Mohammad Hosein) ; Sharif University of Technology
2009
Abstract
As massively multiuser virtual environments (MMVEs) expand in terms of size and user population, they tend toward using P2P architectures as a way to provide scalability without the need for large centralized resources. Distributed hash table (DHT)-based networks have been introduced as a promising option for overlay-based distributed massively multiuser virtual environment applications. However, overlay latency stretch seriously affects MMVE performance where QoS is crucial for real-time user collaboration. This work includes a series of efforts in the alleviation of such undesired latency. Our approach to latency mitigation consists of two phases. First, we propose a position-based ID...
First principles study of the I–V characteristics of the alkane-thiols nano-molecular wires
, Article Current Applied Physics ; Volume 9, Issue 2 , March , 2009 , Pages 367–373 ; Gholami, M. R. (Mohammad Reza) ; Ganji, M. D ; Taghavi, M. M ; Sharif University of Technology
2009
Abstract
This article has been retracted at the request of the Editorial Board of Current Applied Physics. Please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). Reason: The authors have plagiarized part of a paper that had already appeared in J. Phys. Chem. B, 109 (2005) 3334–3339: “Changes of Coupling between the Electrodes and the Molecule under External Bias Bring Negative Differential Resistance, by Xingqiang Shi, Xiaohong Zheng, Zhenxiang Dai, Yang Wang, and Zhi Zeng”. One of the conditions of submission of a paper for publication is that authors declare explicitly that their work is original and has not appeared in a publication elsewhere. Re-use...