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ghavidel-darestani--nasim
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Separaition of Cu 2+ Ions from Aques Medium Using Silica Nano Pore Functionalized Amine Groups Confiend with Ionic Liquid
, M.Sc. Thesis Sharif University of Technology ; Mohammad , Mahmoudi Hashemi (Supervisor) ; Mirzaee, Mohammad (Supervisor)
Abstract
Purification of waste water containing metal ions, is one of major environmental problems which have threaten human’s life, other creatures and even agricultural products by means of polluting suberranean water. Copper ion is one of dangerous heavy metals that exists in potable water and agricultural uses, due to serious problems in health of humans and aquatic. In recent years, different methods for purification of waste water containing heavy metal ions have been published. Right now, thorough these methods such as: filtration, coagulation, precipitation and adsorption are being used, which have their own advantages and disadvantages.In this research, new method for purification of waste...
Measuring customer satisfaction using a fuzzy inference system
, Article Journal of Applied Sciences ; Volume 9, Issue 3 , 2009 , Pages 469-478 ; 18125654 (ISSN) ; Jahromi, A. E ; Sharif University of Technology
2009
Abstract
This study presents a new method called FCSMM (Fuzzy Customer Satisfaction Measurement Method) for measuring individual customer satisfaction using a fuzzy inference system. The main advantage of this method is its simplification in evaluation of Customer Satisfaction Index (CSI) based on simple linguistic statements collected from experienced people. In contrast with assumptions used in other methods such as linear regression principles and predefined criteria weights, the aforementioned statements form the FCSMM computational structure. Since the drivers of satisfaction and dissatisfaction and performance indexes can be simultaneously applied, concurrent direct and indirect customer...
Mechanical & Microstructural Evaluations of (High MFI PP/Low MFI PP)/Organoclay Nanocomposites Influence of Clay Loading, Compatibilizer Loading and Processing Sequence
, M.Sc. Thesis Sharif University of Technology ; Bagheri, Reza (Supervisor)
Abstract
Polymer/layered silicate nanocomposites are good candidates to improve polymer matrices due to enhanced interfaces between nanoclay reinforcement and matrix. So many attempts has been done to improve fabrication methods of these nanocomposites. Polypropylene is a common used engineering material in many industrial applications (general and special). So there is many researches focused on PP/Clay nanocomposites. In this research we tried to investigate the role of clay loading, compatibilizer loading and processing sequence on clay delamination and layer dispersion. We used a blend of two different PPs with different MFI values as matrice. It seems that the blend achieves acceptable...
Design and Build an Acoustic Tweezers and Move up the Polystyrene Particles
, M.Sc. Thesis Sharif University of Technology ; Amjadi, Ahmad (Supervisor)
Abstract
Ultrasound waves have attracted substantial attention due to their potential for trapping the small particles, which cannot be handled by usual tweezers. The acoustic tweezer is a technology that is able to tarp and control the movement of micrometer to millimeter objects by standing or focused sound waves. Acoustic tweezers are the subject of many researches around the world, due to simplicity, cost-effective, biocompatibility and most important better performance in non-transparent optical environments, compared with optical tweezers.In this project, by using a ring piezoelectric and a power amplifier, an acoustic tweezer was designed and constructed. Moreover, the polystyrene particles...
Design of Base Isolated Structures by Endurance Time Method
, M.Sc. Thesis Sharif University of Technology ; Estekanchi, Homayoon (Supervisor)
Abstract
Endurance Time Method (ET) is a dynamic analysis based on the Time History Analysis in which a predefined intensifying excitation would be applied to the structure and then the performance of the structure would be assessed based on the maximum time that the structure could fulfill the predefined criteria. This method has less complications than the other ordinary Time History methods and decreases the calculations. This method could be applied to Seismic Isolated Structures. Seismic Isolation is a method for decreasing seismic response of structures without increasing strength and ductility of the structure. In this Method all or parts of the structure would be separated from the ground...
Reflection optimization of nano-multilayer X-ray mirrors in three-edge energies: Cr-Kα, Co-Kα, and Ti-Kα
, Article Iranian Journal of Physics Research ; Volume 17, Issue 2 , 2017 , Pages 331-336 ; 16826957 (ISSN) ; Khosroabadi, H ; Otoukesh, M ; Sharif University of Technology
Isfahan University of Technology
2017
Abstract
In this paper, a practical simulation method for optimizing of x-ray reflection of nano-multilayer mirrors in three different edge energies: Cr-Kα, Co-Kα, and Ti-Kα is discussed in order to obtain the most reflection based on quarter-wave thickness method (QW). In this method, the reflected x-ray will have a constructive interference, and a peak, called Brag peak, will appear in reflection curve when the tickness of the layer is an odd multiple of the quarter-wave thickness. The quarter-wave thickness is dependent to on the angle and energy of the entrance photon beam. In the mentioned edge energies, for different nano-multilayer mirrors, and for incident angle ranges from 0.5 to 8 degrees,...
Polarity adjustment of a nanosilica-functionalized polyamine modified by ionic liquid for removal of Cu2+ from aqueous solutions
, Article RSC Advances ; Volume 6, Issue 17 , 2016 , Pages 14128-14133 ; 20462069 (ISSN) ; Mahmoodi Hashemi, M ; Ghavidel, N ; Sharif University of Technology
Royal Society of Chemistry
2016
Abstract
The current work deals with modification of the surface of a silica-polyamine with amine-based ionic liquid (IL) and its application for removal of Cu2+ from an aqueous media. The absorbent is simply prepared from commercially available reagents. The material is characterized by FT-IR spectroscopy, thermogravimetric analysis (TGA), N2 adsorption-desorption, and transmission electronic microscopy (TEM). Effects of several parameters on absorption efficiency, as well as activity of the absorbent to other metals, are also investigated. Moreover, the reusability of the absorbent is studied at the optimized condition. © The Royal Society of Chemistry 2016
Categorization of various essential datasets and methods for textual spelling detection and normalization
, Article Iranian Journal of Information Processing Management ; Volume 32, Issue 4 , 2017 , Pages 1143-1170 ; 22518223 (ISSN) ; Abdi Ghavidel, H ; Sharif University of Technology
Iranian Research Institute for Scientific Information and Documentation
2017
Abstract
One of the most primary phases of automatic text processing is spelling error detection and grapheme normalization. Storing textual documents faces several problems without passing this phase, which causes a disturbance in retrieving the documents automatically. Therefore, specialists in the fields of natural language processing and computational linguistics usually make an attempt to sample various data through presenting ideal methods and algorithms in order to reach the normalized data. Several researches have been conducted on English and some other languages, which have been followed by a certain amount of researches on Farsi too. Sometimes, these several researches have remained to be...
Design and Optimization of Nano-multilayer Mirrors For X-ray
, M.Sc. Thesis Sharif University of Technology ; Otukesh, Mohammad (Supervisor) ; Khosroabadi, Hossein (Co-Advisor)
Abstract
One layer mirrors are inexpensive and perform robustly across a broad range of angles, wavelengths, but they exhibit limited reflectivity. Multilayer interference mirrors are routinely used for optical applications requiring high reflectivity and wavelength selectivity. Although they can be designed to achieve a wide range of optical characteristics. One of the main applications of this multilayers in accelerators is guide outpot beamline to receive user. We can optimize these mirrors to give hight reflectivities, and outpot beam with reflect in canal that is equiped this mirrors reach to user. Conditions such as: material of layers, thickness and number of layers, surface roughness, …etc....
A hybrid algorithm for prediction of varying heart rate motion in computer-assisted beating heart surgery
, Article Journal of Medical Systems ; Volume 42, Issue 10 , 2018 ; 01485598 (ISSN) ; Farahmand, F ; Vossoughi, G ; Alizadeh Ghavidel, A ; Sharif University of Technology
Springer New York LLC
2018
Abstract
An essential requirement for performing robotic assisted surgery on a freely beating heart is a prediction algorithm which can estimate the future trajectory of the heart in the varying heart rate (HR) conditions of real surgery with a high accuracy. In this study, a hybrid amplitude modulation- (AM) and autoregressive- (AR) based algorithm was developed to enable estimating the global and local oscillations of the beating heart, raised from its major and minor physiological activities. The AM model was equipped with an estimator of the heartbeat frequency to compensate for the HR variations. The RMS of the prediction errors of the hybrid algorithm was in the range of 165–361 μm for the...
A comprehensive multimodality heart motion prediction algorithm for robotic-assisted beating heart surgery
, Article International Journal of Medical Robotics and Computer Assisted Surgery ; Volume 15, Issue 2 , 2019 ; 14785951 (ISSN) ; Farahmand, F ; Vossoughi, G ; Alizadeh Ghavidel, A ; Sharif University of Technology
John Wiley and Sons Ltd
2019
Abstract
Background: An essential requirement for performing robotic-assisted surgery on a freely beating heart is a prediction algorithm that can estimate the future heart trajectory. Method: Heart motion, respiratory volume (RV) and electrocardiogram (ECG) signal were measured from two dogs during thoracotomy surgery. A comprehensive multimodality prediction algorithm was developed based on the multivariate autoregressive model to incorporate the heart trajectory and cardiorespiratory data with multiple inherent measurement rates explicitly. Results: Experimental results indicated strong relationships between the dominant frequencies of heart motion with RV and ECG. The prediction algorithm...
https://www.sciencedirect.com/science/article/abs/pii/S0032386122006103
, Article Polymer ; Volume 255 , 2022 ; 00323861 (ISSN) ; Shojaei, A ; Salkhi Khasraghi, S ; Karimzad Ghavidel, A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Present work illustrated that the performance of ultrafine silica (Si) particles was improved considerably by rational hybridization with nanodiamond (ND). For this, Si@ND hybrid particles synthesized by chemical hybridization were incorporated into styrene-butadiene rubber (SBR) up to 10 phr. Scanning electron microscopy revealed coarse flower-like clusters for Si@ND nanohybrids, while Si exhibited rigid agglomerates in SBR. Comparing with physical hybrid (Si&ND) and single Si particles, it was revealed that chemical hybrids synergistically improved tensile properties, like 100% and 135% improvements in tensile strength and elongation at break, respectively. Dynamic mechanical analysis of...
Feasibility of infrared tracking of beating heart motion for robotic assisted beating heart surgery
, Article International Journal of Medical Robotics and Computer Assisted Surgery ; Volume 14, Issue 1 , February , 2018 ; 14785951 (ISSN) ; Farahmand, F ; Vossoughi, G ; Ghavidel, A. A ; Rezayat, M ; Sharif University of Technology
John Wiley and Sons Ltd
2018
Abstract
Background: Accurate tracking of the heart surface motion is a major requirement for robot assisted beating heart surgery. Method: The feasibility of a stereo infrared tracking system for measuring the free beating heart motion was investigated by experiments on a heart motion simulator, as well as model surgery on a dog. Results: Simulator experiments revealed a high tracking accuracy (81 μm root mean square error) when the capturing times were synchronized and the tracker pointed at the target from a 100 cm distance. The animal experiment revealed the applicability of the infrared tracker with passive markers in practical heart surgery conditions. Conclusion: With the current technology,...
Automatic Detection and Disambiguation of Metaphorical and Metonymic Concepts
, M.Sc. Thesis Sharif University of Technology ; Bahrani, Mohammad (Supervisor) ; Khosravizadeh, Parvaneh (Supervisor) ; Vazirnejad, Bahram (Supervisor)
Abstract
Disambiguating concepts in language is one of the most challenging tasks in the field of natural language processing and computational linguistics. A sort of these ambiguities can be found in metaphorical and metonymic concepts. In the present study, we try to introduce the structure of the detecting and disambiguating system of metaphor and metonymy. Detection step is based on semantic valency of the verbs occurring within the subject and object positions and the disambiguation step on the key topical concepts. The data of the detection step involves semantic valency of the seven metaphorically and metonymically frequent verbs. First of all, the data were collected by extracting the...
A quartz crystal microbalance biosensor based on polyethylenimine-modified gold electrode to detect hepatitis B biomarker
, Article Analytical Biochemistry ; Volume 661 , 2023 ; 00032697 (ISSN) ; Sepahi, M ; Ahangari Cohan, R ; Khoobi, M ; Hamidi Fard, M ; Ghavidel, A ; Aghasadeghi, M. R ; Norouzian, D ; Sharif University of Technology
Academic Press Inc
2023
Abstract
Biomarkers-based QCM-biosensors are suitable tools for the label-free detection of infectious diseases. In the current study, a QCM-biosensor was developed for the detection of HBsAg. Briefly, anti-HBsAg antibodies were covalently bound to the primary amines after PEI and thiolated-PEI surface modifications of gold-electrode. After RSM optimization, the statistical analysis revealed no significant difference between the immobilization yields of modified layers. Therefore, the PEI-modified QCM-biosensor was selected for further analysis. The PEI-surface was evaluated by FESEM, AFM, ATR-FTIR, and CA measurement. The surface hydrophilicity and its roughness were increased after PEI-coating....
Signal amplification of a quartz crystal microbalance immunosensor by gold nanoparticles-polyethyleneimine for hepatitis B biomarker detection
, Article Scientific Reports ; Volume 13, Issue 1 , 2023 ; 20452322 (ISSN) ; Cohan, R. A ; Sepahi, M ; Sadeqi, M ; Khoobi, M ; Fard, M. H ; Ghavidel, A ; Amiri, F. B ; Aghasadeghi, M. R ; Norouzian, D ; Sharif University of Technology
Nature Research
2023
Abstract
The procedures currently used for hepatitis B (HB) detection are not suitable for screening, clinical diagnosis, and point-of-care testing (POCT). Therefore, we developed and tested a QCM-based immunosensor by surface modification with AuNP-PEIs to amplify the signal and provide an oriented-immobilization surface. The AuNP-PEIs were characterized by ICP-Mass, UV/Vis, DLS, FE-SEM, and ATR-FTIR. After coating AuNP-PEIs on the gold electrode surface, anti-HBsAg antibodies were immobilized using NHS/EDC chemistry based on response surface methodology (RSM) optimization. The efficiency of the immunosensor was assessed by human sera and data were compared to gold-standard ELISA using...
Exploring the potential of moringa leaf extract as bio stimulant for improving yield and quality of black cumin oil
, Article Scientific Reports ; Volume 11, Issue 1 , 2021 ; 20452322 (ISSN) ; Naveed, K ; Ayub, Q ; Alamri, S ; Siddiqui, M. H ; Wu, C ; Wang, D ; Saud, S ; Banout, J ; Danish, S ; Datta, R ; Hammad, H. M ; Nasim, W ; Mubeen, M ; Shah, F ; Fahad, S ; Sharif University of Technology
Nature Research
2021
Abstract
The history of plants to be utilized as medicines is thousands of years old. Black cumin is one of the most widely examined plant possessing naturally occurring compounds with antimicrobial potential. Foliar application of growth stimulators is a successful strategy to enhance yield and quality in many crops. A field study was planned to apply growth stimulator like moringa leaf extract on black cumin crop grown under field conditions using RCB design with three replications. All other agronomic inputs and practices were uniform. The treatments were moringa leaf extract concentrations (10%, 20%), growth stages (40 days after sowing, 80 DAS, 120 DAS, 40 + 80 DAS, 40 + 120 DAS, 80 + 120 DAS,...
Synthesis of silver nanoparticles using Plantago lanceolata extract and assessing their antibacterial and antioxidant activities
, Article Scientific Reports ; Volume 11, Issue 1 , 2021 ; 20452322 (ISSN) ; Guan, Z. H ; Din, A. U ; Ali, A ; Rehman, A. U ; Jan, K ; Faisal, S ; Saud, S ; Adnan, M ; Wahid, F ; Alamri, S ; Siddiqui, M. H ; Ali, S ; Nasim, W ; Hammad, H. M ; Fahad, S ; Sharif University of Technology
Nature Research
2021
Abstract
Silver nanoparticles (Ag. NPs) have shown a biological activity range, synthesized under different environment-friendly approaches. Ag. NPs were synthesized using aqueous crude extract (ACE) isolated from Plantago lanceolata. The ACE and Ag. NPs were characterized and assessed their biological and antioxidant activities. The existence of nanoparticles (NPs) was confirmed by color shift, atomic force microscopy (AFM), and UV–Vis’s spectroscopy. The FT-IR analysis indicated the association of biomolecules (phenolic acid and flavonoids) to reduce silver (Ag+) ions. The SEM study demonstrated a sphere-shaped and mean size in the range of 30 ± 4 nm. The EDX spectrum revealed that the Ag. NPs were...