Search for: pollution
Total 563 records
Effect of cycling development as a non-motorized transport on reducing air and noise pollution-case study: Central districts of Tehran, Article Urban Climate ; Volume 38 , 2021 ; 22120955 (ISSN) ; Karimi, E ; Shahbazi, H ; Shahidzadeh, H ; Sharif University of Technology
Elsevier B.V 2021
The aim of this study was to investigate the possible reduction of air and noise pollution due to the substituent of motorcycles and personal vehicles with bicycles by the theoretical phase and to compare the exposure of a cyclist to noise pollution in using different modes of transportation in the field phase. In the theoretical phase, different scenarios were designed based on a 25% and 50% reduction in the volume of motorcycles and personal vehicles separately, as well as a simultaneous reduction of 50% for motorcycles and personal vehicles. The effect of running these scenarios on reducing air pollution was investigated using emission inventory model and on noise pollution by CadnaA...
Microbial population control in emulsion oil, Article Scientia Iranica ; Volume 6, Issue 5 , 2000 , Pages 111-114 ; 10263098 (ISSN) ; Vossoughi, M ; Sharif University of Technology
Sharif University of Technology 2000
In this paper, controlling microbial degradation of water based metalworking system fluid, emulsion oil, is investigated using glutaraldehyde as biocide. Microbial population was determined through colony counting method. Evaluation and results demonstrate that a 15 day treatment by glutaraldehyde results in higher resistance to microbial deterioration. Analysis of variance through multiple comparison tests was conducted and Least Significant Difference (LSD) was determined. An overall observed paired difference between the first and second treatment is significant; therefore, the first treatment, with an addition of glutaraldehyde every 15 days is suggested
Environmental evaluation and assessment of some important factors of oil contamination in soil around sarkhoun gas refinery of ar abbas, Article Journal of Environmental Studies ; Volume 37, Issue 57 , 2011 , Pages 9-18 ; 10258620 (ISSN) ; Shayegan, J ; Malakouti, M. J ; Akbari, A ; Sharif University of Technology
Hydrocarbon contaminations due to their volatility, solubility and biodegradability properties can enter the vadose zone and adversely influence the soil properties. Recently, some deep and superficial signs of oil pollution have emerged in the soils around the refinery of Sarkhoun. In order to assess the exact type and behavior of pollutants, evaluate the environmental attributes and measure some important factors of oil contamination in this region, and also to see how pollution transfer in the underground environment, this study has been done. Materials & methods Sarkhoun refinery is located 50 kilometers away from ar Abbas in the northeast direction. The area is mostly composed of Marne...
Removal of chromium from aqueous solution using two kinds of polyaniline, Article Journal of Environmental Studies ; Volume 36, Issue 55 , 2010 , Pages 91-98 ; 10258620 (ISSN) ; Borghei, S. M ; Olad, A ; Chaichi, M. J ; Sharif University of Technology
Evaluation of tehran clean air action plan using emission inventory approach, Article Urban Climate ; Volume 27 , 2019 , Pages 446-456 ; 22120955 (ISSN) ; Hassani, A ; Hosseini, V ; Sharif University of Technology
Elsevier B.V 2019
The city of Tehran, the capital of Iran, has been facing severe air quality problems. The air quality of Tehran has been stated as unhealthy over one-third of year during the last two decades. According to the last emission inventory of Tehran for the base year of 2013 mobile sources contribute by about 6, 46, 98, 87, and 70% of total primary SOx, NOx, CO, VOC and PM emission. A number of policies have been implemented in Tehran during the last two decades to tackle the air quality issue. Concentrated mostly on transportation sector, these policies aimed to improve fuel quality and emission performance of vehicles. Nevertheless, there is no quantified evaluation regarding the effectiveness...
The impact of short-term exposure to ambient air pollution on test scores in Iran, Article Population and Environment ; Volume 41, Issue 3 , 2020 , Pages 253-285 ; Vesal, M ; Fatemi Ardestani, S.F ; Sharif University of Technology
Air pollution in urban centers has become a key public concern around the world. Apart from its adverse health effects, air pollution could impact less visible outcomes like cognitive performance. Standardized tests are a fixture of all education settings that are susceptible to pollution shocks because they require high cognitive function. Given that test scores are widely used as signals by parents, employers, and education institutions, pollution shocks could render tests unfair and unreliable. In this paper, we combine pollution data with test scores from a large testing institution in Iran between 2012 and 2017 to quantify the impact of short-term exposure to air pollution on test...
Biodegradation of 4-chlorobenzoic acid by lysinibacillus macrolides DSM54T and determination of optimal conditions, Article International Journal of Environmental Research ; Volume 14, Issue 2 , 2020 , Pages 145-154 ; Sharifi, H ; Ghobadi Nejad, Z ; Hasan Zadeh, A ; Yaghmaei, S ; Sharif University of Technology
Chlorobenzoic acids (CBAs) are recalcitrant and toxic materials which enter the environment directly using pesticides and herbicides, or indirectly through the biodegradation of polychlorinated biphenyl (PCB) compounds. In the conducted study, biodegradation of 4-chlrobenzoic acid was investigated by Lysinibacillus macrolides DSM54T, which had previously been isolated from PCB-polluted soils. Environmental factors including pH, temperature, 4-CBA concentration and inoculation percentage were optimized using response surface methodology (RSM). 58 experiments were designed according to Historical Data, because of the arbitrary selection of experiments, and the combined effects of the...
Implementing spectral decomposition of time series data in artificial neural networks to predict air pollutant concentrations, Article Environmental Engineering Science ; Volume 32, Issue 5 , January , 2015 , Pages 379-388 ; 10928758 (ISSN) ; Zare Shahne, M ; Arhami, M ; Sharif University of Technology
Mary Ann Liebert Inc 2015
A model to predict air pollutants' concentrations was developed by implementing spectral decomposition of time series data, obtained by Kolmogorov-Zurbenko filter, in Artificial Neural Networks (ANN). This model was utilized to separate and individually predict three spectral components of air pollutants' time series of short, seasonal, and long-term. The best set of input variable was selected by evaluating the significance of different input variables while modeling different time series components. Moreover, different possible approaches for constructing such models were examined. Performance of the constructed model to predict air pollutants' level at a central location in Tehran, Iran,...
Design of a mathematical model to minimize air pollution caused by job trips in Mega Cities, Article Scientia Iranica ; Volume 16, Issue 2 B , 2009 , Pages 177-188 ; 10263098 (ISSN) ; Dana, T ; Shafiepour, M ; Mahmoudi, M ; Sharif University of Technology
Urban transportation is one of the main sources of air pollution in mega cities, and urban job related trips can effectively influence the state of air quality. Tehran, the capital of Iran, with a population of 7.3 million, was selected for this study. The present model is designed to investigate the effect on traffic of the business working hours of different occupations and, as a result, on the status of air pollution. Daily job, non-job and recreational trips using the present vehicle fleet is a major factor affecting air pollution in Tehran. In the context of the present study, the necessary information was utilized to define some relations between job trips and pollutant emissions. The...
Permissible emission limit estimation via iterative back-calculation: Case of Assaluyeh energy zone, southern Iran, Article Integrated Environmental Assessment and Management ; Volume 14, Issue 1 , 2018 , Pages 130-138 ; 15513793 (ISSN) ; Saboohi, Y ; Tsatsaronis, G ; Sharif University of Technology
In the present research work, an environmental policy procedure for setting a cap on emissions, as a crucial step in any total emission control system, has been provided and evaluated. It is shown that general regulations on emission intensities and rates do not guarantee that ambient air quality standards are met in intense industrial zones. Local emission limits are necessary to meet ambient air quality standards in these zones. To that end, we used dispersion simulators to back-calculate pollutant concentration thresholds for a large and intense energy system in the Assaluyeh region of southern Iran. Verified modeling results indicate 218 d of pollutant concentration threshold exceedance...
Comparative Study of Biofilters Application for Ammonia Elimination from Industrial Sites, M.Sc. Thesis Sharif University of Technology ; Shayegan, jalaloddin ; Massoudinejad, Mohammad Reza
In this study, for removing ammonia from air, biofilters which is suitable method for removing odors, volatile organic compounds and toxic materials are used. Biofiltration is an efficient, easy and cost effective, environmental friendly process for degradation of ammonia from waste air. Aim of this study is comparative study of biofilters application for ammonia elimination from industrial sites.In order to remove ammonia, two columns with 14 cm inner diameter were used. One of the columns is filled with vermicompost and mineral shell (mineral shell : vermicompost, 1 : 4) and another column is filled with concentrated sludge and scallop (scallop : concentrated sludge, 2 : 3). Each of the...
Dynamic network pricing to contain urban air pollution in stochastic environment, Article Scientia Iranica ; Volume 23, Issue 5 , 2016 , Pages 2005-2022 ; 10263098 (ISSN) ; Aghababazadeh, B ; Babazadeh, A ; Sharif University of Technology
Sharif University of Technology 2016
Network pricing is an effective transportation demand management scheme to reduce traffic and control air pollution, particularly in CBDs. In this study, congested area cordon entry and Park-and-Ride (P/R) facility use are priced for automobiles. Increase in these prices may reduce private auto demand by impelling some of the auto passengers to use public transport from the origin of their trips, or encouraging them to park their cars at the P/R facilities and use buses, or pay the entrance fee and drive inside the cordon. A Markov decision process has been devised to find an optimal policy for pricing the P/R facilities and cordon entry in a city within a variable demand context. This...
A GIS based emission inventory development for Tehran, Article Urban Climate ; Volume 17 , 2016 , Pages 216-229 ; 22120955 (ISSN) ; Taghvaee, S ; Hosseini, V ; Afshin, H ; Sharif University of Technology
Tehran with a population of 8.2 million urban residents, suffers from rapid urbanization in recent years resulting in severe air pollution. The aim of this study is to develop a high resolution emission inventory of primary air pollutants for Tehran. Tehran pollution sources are classified into two major categories. Mobile sources, including vehicles such as passenger car, taxi, motorcycle, pickup, minibus, bus and truck, and stationary sources; consisting of industries, general service and household, energy conversion, terminals and gas stations. The emission of SOx, NOx, CO, VOCs and PM in the year of 2013 were estimated as 37.411 kt, 85.524 kt, 506.690 kt, 83.640 kt and 8.496 kt,...
Separation and recovery of cobalt catalyst from wastewater of PTA unit, Article Reviews in Inorganic Chemistry ; Volume 29, Issue 3 , 2009 , Pages 171-179 ; 01934929 (ISSN) ; Abdolahifar, A ; Jafarbegloo, M ; Sharif University of Technology
The goal of this work is separation and recovery of catalyst residue in wastewater and byproducts of PTA (poly terephetalic acid) unit. Catalyst recovery consists in separating the maximum amount of catalyst and changing the same into valuable compounds. The PTA unit uses cobalt catalyst for oxidation reactions. The byproducts, which contain catalyst, were burned. In the case of metal oxide recovery in the ashes of waste materials, we could solve the problem of the Petrochemical Company. This new method may help us to recover catalyst from wastewater in PTA unit, after which small amounts of ions may be absorbed on a column filled with special absorbent, in such a way that the wastewater...
Characterizing the effect of traffic density on ambient CO, NO2, and PM2.5 in Tehran, Iran: an hourly land-use regression model, Article Transportation Letters ; 2017 , Pages 1-11 ; 19427867 (ISSN) ; Jamshidi, H ; Samimi, A ; Sharif University of Technology
Economic development and population growth in Tehran has increased demand for goods movement and road transportation. This trend has increased mobile source emissions and citizens’ exposure, imposing severe health risks. We used the framework of Land-Use Regression models to quantify the effect of real-time traffic, within buffer distance, on hourly exposure of CO, NO2, and PM2.5. Effect of residential, industrial, and governmental land-use in addition to the effect of pollution sources, such as construction sites and airport were assessed on air pollution. Meteorological variables were also employed to adjust between day variations. R-squared of the models were 38, 27, and 38% for CO, NO2,...
Effects of sulphuric acid pollutant on the shear behaviour and strength of sandy soil and sand mixed with bentonite clay, Article International Journal of Geotechnical Engineering ; Volume 11, Issue 2 , 2017 , Pages 114-119 ; 19386362 (ISSN) ; Khatami, M. H ; Ahmadi, M. M ; Sharif University of Technology
Taylor and Francis Ltd 2017
Mixture of sandy soil and bentonite clay can be used to seal the sanitary landfills and prevent the spread of leachate. Over time, this mixture may be subjected to different landfill contaminants, including acidic pollutants and shear strength variations. The objective of this research was to study the effects of sulphuric acid pollutant with pH values of 7, 3 and 1 on the shear behaviour and strength of clean sand and sand mixed with bentonite clay using common consolidated undrained triaxial tests. The tests results showed that the presence of acid in the soil pore water changes the shear behaviour pattern of the soil. Acid pollutant decreases the clean sand shear strength. In...
A numerical investigation of reactive air pollutant dispersion in urban street canyons with tree planting, Article Atmospheric Pollution Research ; Volume 8, Issue 2 , 2017 , Pages 253-266 ; 13091042 (ISSN) ; Afshin, H ; Farhanieh, B ; Sharif University of Technology
Elsevier B.V 2017
Vegetation acts as a momentum and thermal sink, affecting the mixing of species and temperature-dependent constants of reaction rates. Numerical simulations were performed to investigate the effects of vegetation on the dispersion of reactive pollutants using a computational fluid dynamic (CFD) model coupled with NO-NO2-O3 photochemistry. Moreover, characteristics of temperature and flow fields were analyzed for different aspect ratios and leaf area densities. The results showed that flow is reversed in the presence of trees, and it enhances as leaf area density (LAD) increases; additionally, vegetation creates downward and vortex flows. The results also revealed that the dispersion of...
Environmental policy-making for persian gulf oil pollution: a future study based on system dynamics modeling, Article Energy Sources, Part B: Economics, Planning and Policy ; Volume 12, Issue 1 , 2017 , Pages 17-23 ; 15567249 (ISSN) ; Ahmady, M. A ; Hosseini, S. A ; Mashayekhi, A. N ; Maleki, A ; Sharif University of Technology
Environmental degradation due to economic activities is a key challenge facing sustainable development. The fossil fuel production sector is a very polluting industry. In this research, the future trends of pollution accumulation in the region due to direct/indirect oily discharge into the semi-enclosed area of the Persian Gulf are studied. The purpose of the study was not only to alert policy-makers about potential future threats in the region but also to conduct a trial to develop potential solutions to these problems. Four different environmental cases were studied via the principle of system dynamic modeling simulation. The cases consisted of three situations: relaxed, simple policy, and...
Noise pollution assessment in khoramabad to presenting executive strategies to control or reduce it, Article Journal of Environmental Studies ; Volume 35, Issue 50 , 2009 , Pages 83-96 ; 10258620 (ISSN) ; Nassiri, P ; Sekhavatjo, M ; Abbaspour, M ; Sharif University of Technology
Noise population is one of the most important environmental pollution cases that cause some troubles for inhabitants and employees in city limit and it is seriously considered as a hygienic risky case and even immunity in the world (Abaspour, 1992).The population of khoramabad city as Lorestan state capital has been 305590, on the basis of population estimate in 2003. It has three-city area and it is located at north-southern corridor of country (management and planning organization of Lorestan province 2004).The matter lead to great bulk of jam that pass through the passageway and linking line that cross through khoramabad city and caused diffusion of many kinds of pollution specially noise...
Assessment of emission reduction scenarios with a focus on the impact of vehicle fleets on tehran air quality: case study, Article Transportation Research Record ; Volume 2673, Issue 5 , 2019 , Pages 197-207 ; 03611981 (ISSN) ; Hosseini, V ; Torbatian, S ; Hamedi, M ; Sharif University of Technology
SAGE Publications Ltd 2019
In recent years, the city of Tehran has frequently experienced severe air pollution episodes, and the increase in the use of vehicles has exacerbated this critical situation. It is unclear to what extent each vehicle category contributes to the production of pollution during a pollution event. For this purpose, a combination of the weather research and forecasting (WRF) and the Comprehensive Air Quality Model with Extensions (CAMx) modeling systems was used to simulate the distributions of pollutant concentrations over Tehran in a pollution episode from December 3 to 23, 2017. First, the performance of the modeling system was evaluated with respect to the simulation outputs against...