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bagheri--afsar
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Selective synthesis of conjugated enynes from α-arylalkynols using LiCl-Acidic Al2O3 under solvent-free conditions [electronic resource]
, Article Journal of Chemical Research ; Volume 2002, Number 8, 1 August 2002, pp. 378-380(3) ; Bagheri Marandi, Gholam
Abstract
Free Content Selective synthesis of conjugated enynes from α-arylalkynols using LiCl-Acidic Al2O3 under solvent-free conditions
Selective preparation of fluorescent 1,8-naphthalimides using acidic alumina under microwave irradiation [electronic resource]
, Article Journal of Chemical Research ; 01/2001; 2001(11):485-487 ; Bagheri Marandi, Gholam
Abstract
7H-benzimidazo[2,1-a]benz[de]isoquinolin-7-one compounds were prepared in a selective manner by reaction between o-phenylenediamines and appropriate 1,8-naphthalenedicarboxylic anhydrides using acidic alumina under microwave irradiation
Free vibration of joined cylindrical–hemispherical FGM shells
, Article Archive of Applied Mechanics ; Volume 90, Issue 10 , 2020 , Pages 2185-2199 ; Kiani, Y ; Bagheri, N ; Eslami, M. R ; Sharif University of Technology
Springer
2020
Abstract
Free vibration response of a joined shell system including cylindrical and spherical shells is analyzed in this research. It is assumed that the system of joined shell is made from a functionally graded material (FGM). Properties of the shells are assumed to be graded through the thickness. Both shells are unified in thickness. To capture the effects of through-the-thickness shear deformations and rotary inertias, first-order shear deformation theory of shells is used. The Donnell type of kinematic assumptions is adopted to establish the general equations of motion and the associated boundary and continuity conditions with the aid of Hamilton’s principle. The resulting system of equations is...
Free vibrations of functionally graded material cylindrical shell closed with two spherical caps
, Article Ships and Offshore Structures ; 2021 ; 17445302 (ISSN) ; Kiani, Y ; Bagheri, N ; Eslami, M. R ; Sharif University of Technology
Taylor and Francis Ltd
2021
Abstract
Free vibration response of a cylindrical shell closed with two hemispherical caps at the ends (hermit capsule) is analysed in this research. It is assumed that the system of joined shell is made from functionally graded materials (FGM). Properties of the shells are assumed to be graded through the thickness. Cylindrical and hemispherical shells are unified in thickness. To capture the effects of through-the-thickness shear deformations and rotary inertias, first order theory of shells is used. Donnell type of kinematic assumptions are adopted to establish the general equations of motion and the associated boundary and continuity conditions with the aid of Hamilton's principle. The resulting...
Free vibrations of functionally graded material cylindrical shell closed with two spherical caps
, Article Ships and Offshore Structures ; Volume 17, Issue 4 , 2022 , Pages 939-951 ; 17445302 (ISSN) ; Kiani, Y ; Bagheri, N ; Eslami, M. R ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
Free vibration response of a cylindrical shell closed with two hemispherical caps at the ends (hermit capsule) is analysed in this research. It is assumed that the system of joined shell is made from functionally graded materials (FGM). Properties of the shells are assumed to be graded through the thickness. Cylindrical and hemispherical shells are unified in thickness. To capture the effects of through-the-thickness shear deformations and rotary inertias, first order theory of shells is used. Donnell type of kinematic assumptions are adopted to establish the general equations of motion and the associated boundary and continuity conditions with the aid of Hamilton's principle. The resulting...
A metal-organic framework sustained by a nanosized Ag12 cuboctahedral node for solid-phase extraction of ultra traces of lead(II) ions
, Article Microchimica Acta ; Vol. 181, issue. 9-10 , 2014 , pp. 999-1007 ; ISSN: 0026-3672 ; Ghanbarpour, A ; Behbahani, M ; Bagheri, S ; Bagheri, A ; Sharif University of Technology
2014
Abstract
We show that a metal-organic framework (MOF) sustained by a nanosized Ag12 cuboctahedral node can be applied to selectively extract traces of lead(II) ion from environmental water samples. The MOF was characterized by thermogravimetric and differential thermal analysis, scanning electron microscopy, FTIR, and X-ray diffraction. The effects of pH value, flow rates, of type, concentration and volume of the eluent, of break-through volume and potentially interfering ions on the separation and determination of lead were evaluated. Following desorption with EDTA, Pb(II) was quantified by FAAS. The use of the MOF results in excellent analytical figures of merit including an analytical range from 2...
Cerebrovascular Attack Detection Using Artificial Intelligent Neural Network
, M.Sc. Thesis Sharif University of Technology ; Bagheri Shouraki, Saeed (Supervisor) ; Haj Sadeghi, Khosrow (Co-Advisor)
Abstract
Cerebrovascular Attack has been ranked the second or third of top 10 death causes in Taiwan. It has caused about 13,000 deaths every year since 1986. Once Cerebrovascular Attack (CVA) occurs, it not only leads to the huge cost of medical care, but even death. All developed countries in the world put CVA prevention and treatment in high priority. However, it is necessary to build a detective model to enhance the accurate diagnosis of CVA. From this detective model, CVA classification rules were extracted and used to improve the diagnosis and detection of CVA. This study acquired 2449 valid samples from this CVA prevention and treatment program, and adopted three classification algorithms,...
The effect of reinforcement percentages on properties of copper matrix composites reinforced with TiC particles
, Article Journal of Alloys and Compounds ; Volume 676 , 2016 , Pages 120-126 ; 09258388 (ISSN) ; Sharif University of Technology
Elsevier Ltd
2016
Abstract
In this research, copper matrix composites reinforced with different amounts of titanium carbide particles were produced by mechanical milling and in-situ formation of reinforcements. Morphology and size of milled powders were inspected by scanning electron microscopy (SEM) several times during milling process. Changes in lattice parameter, crystallite size, lattice strain, dislocation density and Gibbs free energy changes (due to increasing in dislocation densities and grain boundaries) in different samples (with different TiC particles contents) were studied by X-Ray Diffraction technique with Cu-kα radiation and using Nelson-Riley method and Williamson-Hall equation. Microstructure of...
Size tuning of Ag‐decorated TiO2 nanotube arrays for improved bactericidal capacity of orthopedic implants [electronic resource]
, Article Journal of Biomedical Materials Research Part A ; Auguest 2014, Vol. 102, Issue 8, P.2625-35 ; Simchi, A. (Abdolreza) ; Bagheri, R ; Sharif University of Technology
Abstract
Surface modification of orthopedic implants using titanium dioxide nanotubes and silver nanoparticles (SNs) is a promising approach to prevent bacteria adhesion, biofilm formation, and implant infection. Herein, we utilized a straightforward and all-solution process to prepare silver-decorated TiO2 nanotube arrays with surface density of 10(3) to 10(4) per µm(2). With controlling the synthesis conditions, hexagonal closed-packed nanotubes with opening diameter of 30-100 nm that are decorated with SNs with varying sizes (12-40 nm) were prepared. Various analytical techniques were utilized to characterize the size, morphology, distribution, valance state, surface roughness, and composition of...
Development of Microextraction Methods
for the Trace Determination of Organic Compounds in Biological and Environmental Media
,
Ph.D. Dissertation
Sharif University of Technology
;
Bagheri, Habib
(Supervisor)
Abstract
The approach of this thesis is to develop and simplify robust microextraction techniques and apply these developed methods to real samples and complex matrices. Firstly, a modified solvent microextraction with back extraction method (SME/BE) combined with high performance liquid chromatography and fluorescence detection (HPLC-FD) was developed for the determination of citalopram in human plasma. Extraction process was performed in a home-made total glass vial without using a teflon ring, usually employed in SME/BE. The evaluation results demonstrated that the calibration curve showed linearity in the range of 1.0–130.0 ng/mL which covers therapeutic window and even lower amounts which is...
Modified Nano Silica a Sorbent for Needle Trap Extraction of PAHs from Water Samples Followed by Gas Chromatography/Mass Spectrometric Determination
, M.Sc. Thesis Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
In this study, a newly designed needle trap device (NTE) containing modified nanosilica as sorbent is used for sampling and preconcentration of some polycyclic aromatic hydrocarbons (PAHs) from headspace of aqueous solutions. An inexpensive modifier, cis-9-octadecenoic acid (oleic acid), which contains a long chain, was used to modify the surface of the nano-scaled silica particles. The hydrophobic interaction between oleic acid and aromatic compounds was the preliminary evidence for extraction of these compounds. After adsorption of selected compounds, thermal desorption was, subsequently, employed to transfer the extracted analytes into a GC–FID. Extraction time and temperature, flow rate...
Tree Optimization in Overlay Multicast
, M.Sc. Thesis Sharif University of Technology ; Movaghar, Ali (Supervisor)
Abstract
One of the main parts of peer-to-peer multicast is the structure of overlay network. Most of the existing works utilize some common parameters for constructing overlay tree. These parameters are bandwidth and delay. The mismatch between current overlay structure and underlying network topology causes severe link stress and then leads to high end to end latency. According to these problems, we propose a new overlay construction algorithm called OLT in this thesis that finds the location of peers and tries to connect peers that are as close as possible. OLT exploits a number of heuristic techniques to reach an optimized tree even in case of peer heterogeneity and high churn rate. Our...
, M.Sc. Thesis Sharif University of Technology ; Alavi, Babak (Supervisor)
Abstract
The measure of success in a company is determined by a high performing workforce that demonstrates the competencies necessary to drive the business success, while meeting the organization's strategic goals. This is where competency-based human resource management becomes important. The main factor contributing to the above noted area is the identification of core competencies. There has been a lot of research in this area during the past few years. Each research demonstrates an approach for the development of critical human resource competency models in an organization. In order to determine the foregoing competency model, the early studies in this area have been focused on the distinction...
Evaluation of The Effect of Molecular Weight, Mixing Approach and Compatibilizer on Morphologhy and Mechanical Properties of PP/PA/Clay Nanocomposite
,
M.Sc. Thesis
Sharif University of Technology
;
Bagheri, Reza
(Supervisor)
Abstract
Polypropylene/clay nanocomposites are considered as a group of widely used nanocomposites in industrial applications due to their desired properties, yet reasonable cost. However, dissimmilar chemical nature of polypropylene and clay do not allow perfect dispersion of silicate layeres in the matrix and thus restricts full advantages of these composites.An earlier investigation in this group considered solving this shortcoming through incorporation of PA6 as an intermediate phase to enhance clay platelets dispersion. The current project follows this route via studing the influence of molecular weight of the PP matrix, compatibilzer and the mixing procedure of the compound. To investigate the...
Marketing Plan for the Products of Esfahan Steel Company
, M.Sc. Thesis Sharif University of Technology ; Shavandi, Hassan (Supervisor)
Abstract
Nowadays, competition in supplying the requirement of the customer having become so important and curtail between the companies, so marketing plays an important role in the progress of the firms. Therefore, business and marketing concept is one the important tools to achieve their potential goals in the target markets. For Esfahan Steel Company because of their product’s quality, marketing is so significant. With respect to put the third forge will be put into operation perfectly in this company, the production will be increased and reach to 3.7 million tones per year. In this research, we develop a Marketing Plan for the products of this company in the international target market
Deposition and Analysis of Indium-Tin-Oxide NanoStructures Using Sputtering
, M.Sc. Thesis Sharif University of Technology ; Rashidian, Bijan (Supervisor)
Abstract
Transparent conductive materials have been widely used in semiconductor technology. Among them all, Indium tin oxide (ITO) has been utilized as electrodes in liquid crystal displays, solar cells, heat reflecting films and gas sensors.In general, the desired properties of transparent conductive oxides are high conductance and transmission. However, due to the complexity of ITO molecular structure, the film properties strongly depend on the depositon parameters.In first part of this thesis, physical properties and electrical characteristic of ITO films, different deposition techniques, and effects of deposition parameters (substrate temperature, pressure, power, etc. ) on film properties are...
A priority of Logic
, M.Sc. Thesis Sharif University of Technology ; Nasrin, Mehdi (Supervisor)
Abstract
Hartry Field argues that meaning-besed approaches to explaining the apriority of certain propositions fail to succeed in their endeavour. He suggests that adoting what one cals a non-factualist view of justification itself removes the mystery of the apriority of such propositions, and sketches what such a view of justification involves. A priori justification is often thought mysterious or out of keeping with a naturalistic view of the world; strong forms of priori justification that involve empirical indefeasibility are often thought especially mysterious. While this is no doubt correct for excessive claims of a priority – for instance, claims to prori acces to features of the physical...
Electrospun Nanofibers and Their Application for Microextraction of Environmental Samples
, Ph.D. Dissertation Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
Novel electrospun nanofibers and their applications as the microextractionsorbents are the centre of this research. Polymeric nanofibers with diameter in the scale of nano-to-micro were prepared by the electrospinning method and employed for microextraction purposes. Two major microextraction methods included solid phase microextraction (SPME) and micro-Solid phase extraction (µ-SPE). In the first work, a novel SPME fiber was fabricated by electrospinning method. A thin stainless steel wire was coated by the network of polymeric nanofibers. The polymeric nanofiber coating on the wire was mechanically stable due to the fine and continuous nanofibers formation around the wire with a three...
Polyaniline Nanowire Networks as Sorbent for Microextraction in Packed Syringes
, M.Sc. Thesis Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
A simple, fast and sensitive method based on microextraction in packed syringe (MEPS), a new format of solid-phase extraction (SPE), as a sample preparation technique in off-line combination with gas chromatography-mass spectrometry (GC-MS) was developed. Polyaniline (PANI) nanowire network was synthesized and used as sorbent of MEPS for the multiresidue determination of selected analytes from triazine, organochlrorine and organophosphorous pesticides in aqueous samples. The PANI nanowires network was prepared using soft template technique and its characterization was studied by scanning electron microscopy (SEM). The use of micelles in this methodology has an important role in the shape of...
Offering a Simple Method to Determine Safe Distance between Gas Pipelines and Vicinal Areas
, M.Sc. Thesis Sharif University of Technology ; Rashtchian, Davood (Supervisor)
Abstract
Sour Gas is more dangerous than sweet gas because of its hydrogen sulfide contents. So it requires more safety considerations. In this project, the effect of wall thickness and design factor of pipeline on the safe distance was examined by using risk assessment method. The safe distance tables for 4 pipelines with different wall thicknesses and design factors were prepared based on operating pressure, pipe diameter and hydrogen sulfide concentration in gas by using PHAST and PHAST RISK softwares. In this project, the depth of cover parameter was considered in safe distance determination. Also the leak of sour gas was simulated by using...