Loading...
Search for:
naseri--amin
0.12 seconds
Total 346 records
Novel microwave-assisted synthesis of porous g-C3N4/SnO2 nanocomposite for solar water-splitting
, Article Applied Surface Science ; Volume 440 , 15 May , 2018 , Pages 153-161 ; 01694332 (ISSN) ; Soleimani, F ; Naseri, N ; Soltaninejad, M ; Montazeri, S.M ; Sadrnezhaad, S.K ; Mohammadi, M.R ; Moghadam, H.A ; Forouzandeh, M ; Amin, M.H ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Highly porous nanocomposites of graphitic-carbon nitride and tin oxide (g-C3N4/SnO2) were prepared through simple pyrolysis of urea molecules under microwave irradiation. The initial amount of tin was varied in order to investigate the effect of SnO2 content on preparation and properties of the composites. The synthesized nanocomposites were well-characterized by XRD, FE-SEM, HR-TEM, BET, FTIR, XPS, DRS, and PL. A homogeneous distribution of SnO2 nanoparticles with the size of less than 10 nm on the porous C3N4 sheets could be obtained, suggesting that in-situ synthesis of SnO2 nanoparticles was responsible for the formation of g-C3N4. The process likely occurred by the aid of the large...
Photoresponse enhancing in nanostructured WO3films by slight change in heating ambient
, Article Journal of Alloys and Compounds ; Volume 693 , 2017 , Pages 871-875 ; 09258388 (ISSN) ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
Providing solar hydrogen as a clean energy resource is one of the human challenges for future. Controlling oxygen vacancies as well as surface morphology in metal oxide semiconductors enables developing PEC H2production in some understood ways. Here, the influence of simple change in annealing atmosphere, air and pure oxygen, on photoresponse of nanocrystalline WO3has been studied completely. Results revealed that such slight change in annealing procedure increases effective surface interface and donor density by 77 and 72%, respectively. These effects and also retarding recombination of photogenerated electro-hole pair resulted in photocurrent enhancement under solar like illumination more...
Introducing a Simulation-Based Model to Improve the Design and Layout of Workstations Inside Airport Terminals in Iran
, M.Sc. Thesis Sharif University of Technology ; Alvanchi, Amin (Supervisor)
Abstract
The airport terminal is difficult to plan and design due to the different components and the intricate complexity of its parts. At the airport terminal, we face a queue system which simulation is always a good way to analyze. In addition, computer simulation using modern softwares with the capability to model different types of systems, including the airport terminal, while being less realistic than analytical models, is less costly than operational Exercise.In this study, a supportive approach for better and specific management of Iranian airport terminal buildings with discrete-event simulation is proposed, considering the need for managing the airport terminals building in the country and...
Performance Management of HSE Management System based on BSC Framework-the Case Study of Mapna Corporation
, M.Sc. Thesis Sharif University of Technology ; Sepehri, Mehran (Supervisor)
Abstract
A Balanced Scorecard (BSC) model is proposed to evaluate performance of Health, Safety and Environment (HSE) management systems. This model includes key performance indicators at three integrated levels. It has been tested and verified in a project-based organization in Iran, active in the area of power and energy. Results show that the company has done well in implementing HSE management processes, but no so well in growth and learning. This model may be used as a basis for comparing different companies and various proposed programs in the field of HSE management systems. The model includes indicators and sub-indicators in each category particularly related to stakeholders, processes, and...
Kinetic Modeling of Hydrocracking of Synthetic Wax from Fischer-Tropsch
, M.Sc. Thesis Sharif University of Technology ; Khorasheh, Farhad (Supervisor)
Abstract
Fischer-Tropsch process (FT ) is one of the most important processes gas-to-liquid (GTL) conversion. This process converts synthesis gas into hydrocarbons. Depending on the catalyst and operating conditions of the process, heavy paraffins (Wax) are the most important products in this process. These products can be used to heavy paraffin catalyst hydrocracking in a process for the production of diesel fuel and gasoline to lighter products are suitable to be converted. The aim of this project is to develop a suitable kinetic model to describe the process of producing heavy paraffin hydrocracking process Fisher - Tropsch to be lighter products. In this regard, each 5 continuous mass model...
Modeling of the Biomechanical Properties of Articular Cartilage
, M.Sc. Thesis Sharif University of Technology ; Firoozbakhsh, Keikhosrow (Supervisor)
Abstract
Articular cartilage Function is vital to joint tasks and its motion. The main biomechanical tasks of articular cartilage are a) the distribution of loads occurred in joints; b) providing joints with frictionless surface. The particular mechanical properties of articular cartilage make it possible for the Cartilage tissue to do its duty successfully. The biological factor that causes articular cartilage to damage is still unknown. It is believed that mechanical factors are the main reason for the cartilage destruction in osteoarthritis. Factors like age, heavy exercises and impact can begin tissue destructions and result in change in mechanical properties. To study the process of the...
Line Simplifcation Using the Hausdorff Distance as Error Metric
, M.Sc. Thesis Sharif University of Technology ; Zarei, Alireza (Supervisor)
Abstract
Due to recent advancements and wide usage of location detection devices, huge amount of data are collected by GPS and cellular technologies which exhibits moving objects trajectories. Using this information, it is possible to track a set of objects over a long period of time, as happens for instance in studying animal migration. Always, in these situations it is undesirable or even impossible (due to process and storage limits) to store the complete stream of positioning data. Then, simplifying a trajectory as a data reduction technique is the option for resolving such problems. Moreover, there is an increasing interest in queries capturing ”aggregate” behavior of trajectories as groups like...
Optimizing Co Nanoflakes Growth Parameters and Modifying Their Electro-catalytic Performance Using Carbon Nanostructures for Water Oxidation Reaction
, M.Sc. Thesis Sharif University of Technology ; Naseri, Naimeh (Supervisor)
Abstract
Ease of solar hydrogen production using water splitting and its environmental benefits, distinct hydrogen from other energy carriers. Hydrogen is the most abundant material in the world that make up more than 90% of the world compounds. So applying this material as a clean fuel is the best way to prevent environmental problems caused by fossil fuels. For efficient hydrogen production from water, a suitable electrocatalyst with low overpotential, high mechanical strength and reasonable catalytic activity must be utilized. In this research, cobalt based electrocatalyst was used considering that electrodepositon conditions play an important role in its final efficiency. On the other hand,...
Synthesis, Characterization and Optical Study of a New Heterobinuclear Bis(Cyclometalated) Complex Containing Pt(II) and Au(I)
, M.Sc. Thesis Sharif University of Technology ; Jamali, Sirous (Supervisor)
Abstract
The bis-cyclometalated platinum(II) complexes [Pt(ptpy)2], 3, and [Pt(fppy)2], 4, in which, ptpy = 2-(p-tolyl)pyridine and fppy = 2-(2,4-difluorophenyl)pyridine have been prepared. The reaction of 3 with one equiv [Au(PPh3)]+ (prepared from the reaction between AuCl(PPh3) and AgOTf) gave the heterobinuclear complex [Pt(ptpy)2Au(PPh3)].OTf, 5, by formation of a Pt→Au dative bond. The structure of all complexes were characterized using multinuclear NMR spectroscopy in solution phase and the structures of 4 and 5 determined using X-ray crystallography in solid state. The structure of heterobinuclear complex 5 shows an unusual Pt-Au bond that supported by Au-Cipso bond. The absorption and...
Evaluation and Optimization of Physical Properties of Graphene Oxide Nano Flakes to Confront Antibiotic Resistant Bacteria
, M.Sc. Thesis Sharif University of Technology ; Naseri, Naimeh (Supervisor)
Abstract
Antibacterial resistance towards existing antibiotics has become a major problem in medicine and health in recent years. Therefor it has become a challenge for scientists in different fields to find new antibiotics. Graphene and its derivatives, specially Graphene Oxide has gained attention in this area due to their unique physical properties. Graphene Oxide is considered to be a promising 2D nanomaterial for biomedical applications, due to its ease of production, stability in water, unique chemical and mechanical properties and its biocompatibility compared to other nanomaterials. In this study, graphene Oxide was synthesized using modified Hummers’ method. In order to investigate the...
Modifying Hole Transport in Branched hematite Nanostructures for Photoelectrochemical Water Splitting
, M.Sc. Thesis Sharif University of Technology ; Naseri, Naimeh (Supervisor)
Abstract
Regarding increasing world population, air pollution and depletion of fossil fuels supplies, hydrogen production via photoelectrochemical water splitting is a promising approach for providing a clean and renewable source of energy. Hematite (α-Fe2O3), the most common natural form of iron oxide, with a suitable band gap, high stability, earth-abundant nature and low cost has been widely acknowledged as a photoanode. However, intrinsic drawbacks of hematite like low electrical conductivity, short hole diffusion length and high recombination rate of electron-hole pairs hinder its photoelectrochemical performance with high efficiency. In this research, hematite nanostructures were synthesized...
Studying Graphene Oxide Nanoflakes Size Effect on Antibiotic Resistant Bacteria
, M.Sc. Thesis Sharif University of Technology ; Naseri, Naimeh (Supervisor)
Abstract
Two-dimensional (2D) nanomaterials are ultrathin nanomaterials with a high degree of anisotropy and chemical functionality. Research on 2D nanomaterials is still in its infancy, with the majority of research focusing on elucidating unique material characteristics and few reports focusing on biomedical applications of 2D nanomaterials. Here we report the properties and application of 2Dnanomaterials in field of bio technology while used main material in our project is graphene oxide for investigating its antibacterial properties. Because the properties of graphene oxide (GO)-based materials strongly depend on the lateral size and size distribution of GO nanosheets; therefore, GO and its...
Measure for Macroscopic Quantumness via Quantum Coherence and Macroscopic Distinction
, M.Sc. Thesis Sharif University of Technology ; Raeisi, Sadegh (Supervisor)
Abstract
One of the most elusive problems in quantum mechanics is the transition between classical and quantum physics. This problem can be traced back to the Schrodinger's cat. A key element that lies at the center of this problem is the lack of a clear understanding and characterization of macroscopic quantum states. Our understanding of Macroscopic Quantumness relies on states such as the Greenberger-Horne-Zeilinger(GHZ) or the NOON state. Here we take a first principle approach to this problem. We start from coherence as the key quantity that captures the notion of quantumness and demand the quantumness to be collective and macroscopic. To this end, we introduce macroscopic coherence which is the...
Modifying TiO2 Photoanodes by Co-Pi Electrocatalyst for Solar H2 Production
, M.Sc. Thesis Sharif University of Technology ; Naseri, Naimeh (Supervisor)
Abstract
Currently, fossil fuels are the primary source of energy in the world. The increasing human need for energy and the limited resources of fossil fuels and their environmental side effects necessitate the search for other sources of energy. Considering its abundance and eco-compatibility, using solar energy is one of the best candidates for future. One of the methods to use solar energy is to convert and store it as hydrogen fuel by photoelectrochemical cells. In recent years, the main challenge with the production of hydrogen fuel in photoelectrochemical is optimizing them to increase efficiency. For this purpose, various approaches have been proposed such as the fabrication and use of...
Coherence-based characterization of macroscopic quantumness
, Article Physical Review A ; Volume 103, Issue 3 , 2021 ; 24699926 (ISSN) ; Raeisi, S ; Sharif University of Technology
American Physical Society
2021
Abstract
One of the most elusive problems in quantum mechanics is the transition between classical and quantum physics. This problem can be traced back to Schrödinger's cat thought experiment. A key element that lies at the center of this problem is the lack of a clear understanding and characterization of macroscopic quantum states. Our understanding of macroscopic quantumness relies on states such as the Greenberger-Horne-Zeilinger (GHZ) or the NOON state. Here we take a first-principle approach to this problem. We start from coherence as the key quantity that captures the notion of quantumness and require the quantumness to be collective and macroscopic. To this end, we introduce macroscopic...
Estimating Protein-Protein Interaction Network Similarity through Sampling
, M.Sc. Thesis Sharif University of Technology ; Beigy, Hamid (Supervisor)
Abstract
In examining protein-protein interaction networks, we often encounter similar and repetitive schemes. Examination of these designs, which often appear in the form of motifs and similar patterns, reveals important information such as the type of protein linkage and many of the internal similarities between these networks. The ability to recognize these similarities plays an important role in identifying the function of genes, recognizing the relationships between diseases, and making drugs. We know that exact algorithms for examining subgraph isomorphism are np-hard and time-consuming and infeasible in large networks; Therefore, in practice, approximate and heuristic algorithms are used and...
Fair resource allocation in Ad hoc networks in the presence of delay
, Article INDICON 2008 IEEE Conference and Exhibition on Control, Communications and Automation, Kanpur, 11 December 2008 through 13 December 2008 ; Volume 1 , 2008 , Pages 159-164 ; 9781424427475 (ISBN) ; Haeri, M ; Sharif University of Technology
IEEE Computer Society
2008
Abstract
In this paper, the problem of resource allocation at an Ad hoc network with nodes not using any infrastructure to cooperate with each other is considered. By using a simple interference model in wireless links, the convergence and stability of a fair resource allocation scheme in the absence of delay is investigated. Also, the local stability of the scheme in the presence of upper-bounded delay is verified. Simulations results illustrate the convergence and fairness of this scheme considering different initial states for different sources. The performance of the scheme in the presence of different disturbances for each flow in transient and steady state along with its local stability in the...
Studying Supercapacitive Performance of Cobalt-based Hierarchical Nanostructures
, M.Sc. Thesis Sharif University of Technology ; Naseri, Naimeh (Supervisor)
Abstract
One of the pillars of reaching a steady development is to utilize sustainable energies. In order to make use of these modern means of energy, appropriate energy storage devices are inevitable. One of the families of these devices is the supercapacitors. Moving toward the 4th industrial revolution, we are encountering modern technologies such as internet of things and wearable electronics. Therefore, designing and fabricating microsupercapacitors is of paramount importance in order to reduce the weight and size of these devices. Cobalt and nickel are considered as two important elements to be used in synthesizing supercapacitive materials and composites, because of their good electrochemical...
, M.Sc. Thesis Sharif University of Technology ; Alvanchi, Amin (Supervisor)
Abstract
Limited water resources in Iran have made dams an important part of the country’s infrastructure. As a result of the large number of in-progress and expected dam projects in the country, consideration of sustainability factors during planning, construction and operation phases of dam projects can create significant economical, social and environmental impacts in the long term. To come up with an inclusive sustainable development, new sustainability assessment approaches seek for sustainable development at the entire project’s life-cycle; they are looking for sustainable development at all design, construction, operation, maintenance and even demolition phases. In this research we have...
Dynamic Planning of Transmission Expansion
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Hamid (Supervisor)
Abstract
Goal of this project is to present a method for dynamic transmission planning in restructured environment by system regulator. Congestion, fair competition in power market, stakeholders’ desires in transmission expansion, transmission investment traits, creating incentive for investment and transcos revenue are considered in this work. Presentation of methodology for reliability evaluation is necessary because of increasing uncertainties due to restructuring. Remedial action method is suggested for uncertainties analysis and reliability index presented for measuring degree of reliability. The method has been applied to the IEEE 14-bus system. ...