Search for: environmental-pollutions
Total 66 records
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
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
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...
Experimental Investigation of Mechanical Behavior of Structural Concrete with Combination of Waste Glass and Silica Fume, M.Sc. Thesis Sharif University of Technology ; Khaloo, Ali Reza
Concrete is the second most structural material in the world. So attention and promotion of the concrete mix design with respect to variable issues and requirements, is very important. On the other hand, these days environment and its pollution has become very popular discussion. Waste-glass which is produced by human products is one of the environmental pollutants. In this thesis it replaces some aggregate in concrete and it can reduce the level of this material in the world. Also we study effects of silica-fume as cement replacement and properties enhancer in our concrete mix design and see how it can ...
The Kinetic and Mechanism Evaluation of Photocatalytic Degradation of Environmental Pollutants Using Modified Nanocomposites, Ph.D. Dissertation Sharif University of Technology ; Gholami, Mohammad Reza
Different nanocomposites were prepared based on the carbon nitride, structures and metal organic framework. The photocatalytic activities of a group of metal-organic metal frameworks were evaluted. Next step, the combination of binary and ternary composites based on carbon nitride/metal-organic frameworks structures with other semiconductors such as oxyacid, bismuth oxy halide and ferrite spinel was used. In addition, synthesis of varius type of metal oxides structures with metal organic framework precursors has also been another perpuse of this thesis.The catalytic and photocatalytic activities of designed nanocomposites were performed for a redox process (4-nitrophenol (4-Nip) to...
Criteria of Choosing Intersection or Roundabout Based on Delay Time, Fuel Consumption, and Environmental Factors, M.Sc. Thesis Sharif University of Technology ; Nassiri, Habibollah
Nowadays, there are three factors in traffic issues, which are very important. These factors are delay time, fuel consumption and environmental pollution. A good choice of the type of traffic nodes (intersection and roundabout) can play an important role in reducing some of the traffic problems such as: the amount of vehicles' delay time, energy consumption and pollution due to the transport system. In this study, we try to identify factors that influence delay time, fuel consumption and air pollution in different types of intersections and roundabout. According to previous studies, these factors were such as: variables of each route volume, distribution of through, right turn and left turn...
Comparison of Performance of Rice Husk Ash in Cement Mixtures Compared with other Artificial Pozzolan, M.Sc. Thesis Sharif University of Technology ; Khalu, Alireza
Growing production of cement and concrete in developing countries like Iran in addition to high amounts of energy consumption and pollutants formation through production of cement has motivated researchers to partially replace it with suitable additive materials. In this study, the chemo-physical and microstructural properties of rice husk ash as an agricultural waste and its performance in cement mixtures as a pozzolan is experimentally investigated. Parameters influencing the pozzolanic properties of this material that are studied include the effect of acid leaching before pyro-processing, heating rate, temperature, retention time, and cooling rate. Additionally, this material is compared...
A Sol-Gel-bonded Coating Deposited on the Surface of Stainless Steel Wire for Solid Phase Microextraction of Environmental Pollutants, M.Sc. Thesis Sharif University of Technology ; Bagheri, Habib ; Es-haghi, Ali
A novel SPME fiber was prepared using sol-gel technology with ethoxylated nonylphenol as a precursor and used for development of a headspace solid phase microextraction coupled with gas chromatography-mass spectrometry method for quantification of 13 priority polycyclic aromatic hydrocarbons in water samples. The fused silica is the material that has recently been used as a substrate in sol-gel works for preparation of SPME fibers. Given that its drawbacks such as breakability and fragility which make the work tedious and time consuming¬, in this survey stainless steel wires were chosen as a substrate for coating the sol-gel film on them. The fibers made from steel are vary sturdy and aren’t...
Optimization and Scheduling Smart Energy Hub under Uncertainty of Distributed Energy Resources, M.Sc. Thesis Sharif University of Technology ;
Besides increasing the installation of distributed generation plants, investigating multi-carrier energy systems leads recent studies to focus on Smart Energy Hub (S.E.Hub) systems. S.E.Hub systems incorporate several modules which optimal size and operation of each have already attracted a great deal of research. Uncertainty in the modelling of these modules is an imperative factor that has not been associated in S.E.Hub models properly. To build up a more precise framework for S.E.Hubs, here we present a stochastic model for electricity and natural-gas prices, electricity and heat demands, and emission costs. In this paper, S.E.Hub operates based on minimizing weighted sum function which...
Synthesis and Characterization of TiO2 Based on Carbon (Activated Carbon and Carbon Nanotube) and Investigation of its Catalytic Activity on Environmental Pollutions, M.Sc. Thesis Sharif University of Technology ; Gholami, Mohammad Reza
Pure NanoParticles of TiO2 and Nanocomposite catalysts of TiO2 , activated carbon (TiO2/AC) and multi-walled carbon nanotube (TiO2/MWCNT) were prepared by a sol –Gel method using TetraisoPropylorthotitanat (Tipt) as a precursor. The catalysts were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), diffuse reflectance uv-vis spectroscopy (DRS) and N2 adsorption – desorption measurements. The photoactivity of samples was evaluated by Acid Blue 92 (AB 92) degradation. The analysis results show that compared with pure Nanoparticles of TiO2, the spherical – shaped TiO2 particles are well – dispersed in TiO2/AC. In TiO2/MWCNT, the coating has special mechanism that...
Synthesis of new Modified Composites Based on Nanoporous Materials and their Application in Environmental Pollutant Degradation, M.Sc. Thesis Sharif University of Technology ; Gholami, Mohammad Reza
In this projekt, nanophotocatalysts containing metal oxides and oxy-acids based on the nanoporous materials were synthesized. The photocatalytic properties of the prepared samples were evaluated by the photodegradation of day moleculs in photocatalytic systems. The catalytic results revealed that Ag3VO4/Cu-MOF/rGO exhibits noticeably an improvement in both efficiency and rate of AB92 photodegradation in comparison with the pure Ag3VO4. Using different scanning mechanisms for the catalytic properties of the synthesized nanocomposites, it was clearly demonstrated that the anionic superoxide plays a decisive role. Reduction of 4-NP in the presence of NaBH4 was also used to investigate...
Synthesis, Characterization and Kinetic Study on Novel Catalysts Supporting Nanoporous Titanium Dioxide for Degradation Environmental Organic Pollutants, Ph.D. Dissertation Sharif University of Technology ; Gholami, Mohammad Reza ; Taghavinia, Nima
Several nanostructured photocatalysts were prepared by sol-gel, hydrothermal and precipitation methods. The products were characterized by X-ray diffraction (XRD), nitrogen adsorption, UV-VIS diffuse reflectance spectroscopy, fourier transform infrared absorption spectroscopy (FT-IR), transmission electron microscopy (TEM), scanning electron microscopy (SEM). Their Photocatalytic activities were evaluated by degradation of organic pollutants in liquid-solid system. In this research work, the influence of metal oxide, copper oxide, on structure of nanocrystalline mesoporous titanium dioxide were evaluated. Different molar percentages of copper oxide on the surface of titanium dioxide were...
Synthesis and Characterization of the Improved Nanocomposites Based on Graphene and Their Mechanism and Kinetic Investigation in the Environmental Pollutant Degradation, M.Sc. Thesis Sharif University of Technology ; Gholami, Mohammad Reza
In this project the RGO/Ag2O/g-C3N4 nanocomposite was synthesized, and characterized by different technique such as SEM, XRD, and FT-IR. Then its photocatalytic activity was investigated. The degradation percent for Acid-Blue 92 by this photocatalyst was estimated 81 in 45 minutes. Afterward, the photocatalyst activity was determined in different pH including 4, 7, 10. The best result was for pH=7. Then, the increasing concentration of dye were investigated and the results show that by increasing the concentration of 10 to 30 ppm, the photocatlytic activity decreased. Photocatalytic degradation process of AB92 were also carried out at different amount of photocatalyst. The mechanism of...
On The Chemo-Physical and Microstructural Properties of Rice Husk Ash and Its Performance in Cement Mixtures, M.Sc. Thesis Sharif University of Technology ; Khalu, Alireza
Growing production of cement and concrete in developing countries like Iran in addition to high amounts of energy consumption and pollutants formation through production of cement has motivated researchers to partially replace it with suitable additive materials. In this study, the chemo-physical and microstructural properties of rice husk ash as an agricultural waste and its performance in cement mixtures as a pozzolan is experimantally investigated. Parameters influencing the pozzolanic properties of this material that are studied include the effect of acid leaching before pyro-processing, heating rate, retention time, and grinding time. Additionally, this material is compared with other...
Synthesis of Modified Nanocomposite Based on Metal Organic Frameworks for Kinetic Study of Environmental Pollutant Elimination, M.Sc. Thesis Sharif University of Technology ; Gholami, Mohammad Reza
An environmentally friendly heterogeneous ternary carbon dots (CDs)/MIL-88B (Fe)/Bi2S3 nanocomposite was synthesized by a multistep method. In this study, we have studied low-temperature calcination with relatively inexpensive reactants. Fabricated nanocomposite structures were characterized by FT-IR, XRD, EIS, SEM, BET, and TGA techniques, demonstrating the decoration of the Bi2S3 on the CDs/MIL-88B (Fe) nanocomposite surface. MOF templating has been chosen as a systemic method for limited size CD formation inside MIL-88B (Fe) pores. The CD arrays also revealed an excellent efficacy for catalytic and photocatalytic applications. According to the experimental results, CDs/MIL-88B (Fe)/Bi2S3...
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
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....
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
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...
Kinetic Investigation of the Degradation of Environmental Pollutant in the Presence of TiO2 Nanoparticle on Carbon Nanotube, M.Sc. Thesis Sharif University of Technology ; Gholami, Mohammad Reza ; Rahman Setayesh, Shahrbanoo
The present work is based on the, synthesis and investigation of photocatalytic activity of TiO2, TiO2/MWCNT, ZnO and ZnO/MWCNT nanostructures. The nanostructures were prepared using multi-walled carbonnanotubes (MWCNT) as templates.The SEM images of TiO2 and ZnO nanoparticles and TiO2/MWCNT andZnO/MWCNT showed that nanosize TiO2 and ZnO particles homogeneously and densely supported on the surfaces of multiwall carbon nanotubes the photocatalytic activity of the TiO2, TiO2 /MWCNT, ZnO and ZnO/MWCNT was examined by the degradation of Basic Blue 41(BB41) under UV and Vis lights. The optimum conditions for degradation of BB41 on TiO2 where found to be: calcination temperature (450 °C), dye...
Kinetics Investigation of Photocatalytic Degredation of Environmental Organic Pollutants Using ZnO-Zeolite Nano Composites, M.Sc. Thesis Sharif University of Technology ; Gholami, Mohammad Reza ; Sajadi, Ali Akbar
ZnO nano particles and mordnite zeolite nano particles were prepared by precipitation method and hydrothermal method,respectively. The influence of solvent and surfactant in ZnO nano particles synthesis were studied to reform the structure of nano particles.These nano particles were based on different supports to improve and enhance their photocatalytic activities. Synthesized catalysts characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform-infra red spectra (FTIR), UV-Vis spectroscopy and BET techniques. To investigated photocatalytic activity of the synthesized catalysts under UV irradiation, they were used to degradation bio-environmental...
A Superhydrophobic Melamine Formaldehyde Sorbent for Micro Extraction of Pollutants from Aquatic Media
Sharif University of Technology
In this project, melamine formaldehyde was chosen as initial substrate for its high porosity. Then for having superhydrophobic surface, surface functional groups were silanized and deactivated as a result. It was assumed that high porosity of prepared sorbent and its nonpolar nature, can increase extraction efficiency. To study extraction efficiency of the prepared sorbent, it was filled inside a needle and used for needle-trap head-space extraction of BTEX (abbreviation for Benzene, Toluene, Ethylbenzene and Xylenes). Needle packed with sorbent was held on headspace of sample containing BTEX and head- space was pumped with a peristaltic pump. Pumping introduces fresh sample to sorbent...
Modified Zeolitic Nanostructures: Synthesis, Characterization and the Investigation of Their Catalytic-Sorption-Antibacterial Applications, Ph.D. Dissertation Sharif University of Technology ; Gholami, Mohammad Reza ; Gobal, Fereydoun
Modified zeolitic nanostructures were prepared by sol-gel, hydrothermal and coprecipitation methods. At first step, natural zeolite was used as a support for preparing the Ag/AgBr/TiO2 photocatalysts. Their photocatalytic properties were studied by degradation of pollutants and microorganism inactivation at the presence of different illumination source. These processes were mechanistically investigated and the results were explained. At second step, mordenite anocrystals, which synthesized by hydrothermal method, were used as an effective support to prepare the AgX/TiO2/MOR photocatalysts. Photocatalytic degradation of an azo dye performed over these nanocomposites and a mechanism suggested...