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Nanocomposite of chitosan/gelatin/carbon quantum dots as a biocompatible and efficient nanocarrier for improving the Curcumin delivery restrictions to treat brain cancer
, Article International Journal of Biological Macromolecules ; Volume 242 , 2023 ; 01418130 (ISSN) ; Pourmadadi, M ; Shamsabadipour, A ; Mashayekh, P ; Sharif University of Technology
Elsevier B.V
2023
Abstract
Curcumin (CUR) is among the most appropriate and natural-based anticancer drugs that can be applied effectively treat different classes of cancers. However, CUR suffers from a low half-life and stability in the body, which has restricted the efficacy of its delivery applications. This study is dedicated to introducing the pH-sensitive nanocomposite of chitosan (CS)/gelatin (GE)/carbon quantum dots (CQDs) as an applicable nanocarrier for enhancing CUR half-life and its delivery restrictions. The CS/GE hydrogel was synthesized by the physical crosslinking method, which improves the biocompatibility of this hydrogel. Moreover, the water-in-oil-in-water (W/O/W) double emulsion approach is...
Surface modification of GO/PVDF composite membrane by MXene/protonated g-C₃N₄ nanosheets hybrids with improved dye separation and antifouling properties
, Article Polymer Engineering and Science ; Volume 64, Issue 2 , 2024 , Pages 565-576 ; 00323888 (ISSN) ; Tarkhani, M ; Mousavi, S. A ; Asadollahi, M ; Sharif University of Technology
Wiley
2024
Abstract
Graphene oxide-polyvinylidene composite membranes were fabricated via the phase inversion technique. Then, GO-PVDF membrane with highest water flux was achieved via surface modification with 2-D MXene and 2-D MXene /protonated 2-D g-C₃N₄ nanosheets hybrid via vacuum filtration of an aqueous dispersion of MXene and MXene-protonated g-C₃N₄ nanosheets hybrid, respectively, on GO-PVDF membrane support to improve filtration efficiency and antifouling properties. The membranes were designated as MXene/GO-PVDF (M2) and MXene-protonated g-C₃N₄/GO-PVDF(M3). XRD, SEM, and FTIR analysis were used for characterization. The results showed that the performance of both MXene /GO-PVDF and MXene-...
A Scan Chain-Based Aging Monitoring Scheme for Detection of Recycled Chips
, M.Sc. Thesis Sharif University of Technology ; Hesabi, Shahin (Supervisor)
Abstract
Today's latest technology integrated circuits are manufactured for a wide range of applications. With the constant increase in the usage rate of integrated circuits, designing a high reliable system is of utmost importance. The avoidance of counterfeit components is a major challenge of hardware security and trust. Counterfeit components cause lower performance and reduced life span. They are of great concern to the manufacturers and consumers of electronic systems, impacting the security and reliability of these systems. If these parts end up in critical applications like medical systems, satellites, aerospace, or power plants, the results could be catastrophic. So far, there are different...
Reliability assessment of distribution system with the integration of photovoltaic and energy storage systems
, Article Sustainable Energy, Grids and Networks ; Volume 28 , 2021 ; 23524677 (ISSN) ; Esmaeili Nezhad, A ; Moeini Aghtaie, M ; Fotuhi Firuzabad, M ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
With the current focus on energy and the environment, efficient integration of renewable energies, especially solar energy into power systems, is becoming indispensable. Moreover, to fully capture solar potentials and to recognize the unique characteristics associated with solar energy in power systems reliability assessment, a profound investigation is needed. Accordingly, this paper attempts to establish a comprehensive analytical approach for modeling the reliability of a hybrid system (Photovoltaic (PV) system with Energy Storage System (ESS)). To this end, the output of the PV system is modeled by a multi-state model, and the ESS system is modeled as a two-state Markov model. Moreover,...
Developing a Framework for Providing the Flexibility of Active Consumers of Energy Distribution Networks
, M.Sc. Thesis Sharif University of Technology ; Moeini Aghtaie, Moein (Supervisor)
Abstract
The power systems’ net-load variability and uncertainty would aggravate significantly as the penetration of Renewable Energy Resources (RERs) in power systems increases. In response, power system researchers have introduced a new concept, namely flexibility, to quantitatively and systematically deal with unavoidable features of RERs. In power distribution systems as the connection point of power systems with customers, there are many opportunities for improving the flexibility level of systems. Nowadays, the emergence of prosumers has created new opportunities for distribution system operators in providing the system with different services of flexibility in distribution systems. Therefore,...
Determination of Saffron Adulteration Thorough the Package Using Hyperspectral Imaging and Chemometric Techniques
, M.Sc. Thesis Sharif University of Technology ; Parastar Shahri, Hadi (Supervisor)
Abstract
These days, food authenticity has become a major challenge because food health directly affects human health. The importance of authenticity is highlighted when we are faced with foods with higher nutritional and economic value. Saffron is an important example of spices because in addition to having food coloring and flavoring properties, it also has numerous health benefits, but it has limited production and high price. Therefore, with the options available and cheaper to be replaced. Thus, among the various spices, cheating in saffron has the fourth place. Hyperspectral Imaging (HSI) has been developed for food safety industrial applications. This technique combines spectroscopy and...
Enhanced visible-light photocatalytic oxidative desulfurization of model fuel over Pt-decorated carbon-doped TiO2 nanoparticles
, Article Environmental Science and Pollution Research ; Volume 31, Issue 12 , 2024 , Pages 18188-18199 ; 09441344 (ISSN) ; Larimi, A ; Jiang, Z ; Lotfi, M ; Ghotbi, C ; Khorasheh, F ; Sharif University of Technology
NIH
2024
Abstract
Modification of photocatalysts to improve their adsorption and photocatalytic activity in the oxidative desulfurization of liquid fuels has been reported by many investigators. In this study, Pt-decorated carbon-doped TiO2 nanoparticles were synthesized by hydrothermal and photo-deposition techniques and were subsequently used in photocatalytic oxidative desulfurization of dibenzothiophene (DBT) in n-heptane as a simulated liquid fuel with methanol as the extracting solvent. Carbon-doped TiO2 was first synthesized by a simple self-doping method. Pt was then loaded by a photo-deposition technique. The synthesized photocatalysts (labeled as YPt-CT where Y is percent Pt loading) were...
Flexibility provision of residential energy hubs with demand response applications
, Article IET Generation, Transmission and Distribution ; Volume 16, Issue 8 , 2022 , Pages 1668-1679 ; 17518687 (ISSN) ; Moeini Aghtaie, M ; Hadi, M. B ; Sharif University of Technology
John Wiley and Sons Inc
2022
Abstract
Smart grids help local distribution companies (LDCs) facilitate the communication between grid operators and residential prosumers. While the prosumers are striving to optimize their daily load profile by home energy management systems (HEMSs) deployment, the LDCs attempt to enhance the operation of the grid in an efficient way and decrease network losses. This paper attempts to develop a new bi-level probabilistic optimization framework wherein an HEMS optimizes its respective daily load profile, and determines its flexibility provision, which is communicated to an LDC. In the proposed framework, a decentralized approach is used to achieve the flexibility product, which is the modulation of...
Designing a new procedure for participation of prosumers in day-ahead local flexibility market
, Article International Journal of Electrical Power and Energy Systems ; Volume 146 , 2023 ; 01420615 (ISSN) ; Moeini-Aghtaie, M ; Hadi, M. B ; Sharif University of Technology
Elsevier Ltd
2023
Abstract
With the high penetration of Renewable Energy Resources (RERs) into power systems, distribution systems are facing various challenges due to their intermittency and uncertainty. One of the ways to cope with uncertainty and variability of the RERs is utilizing flexibility by market tools to enable active system management. Local Flexibility Markets (LFMs) provide opportunities to trade flexibility among distribution system operators and other participants (e.g., aggregators) in an economically efficient way. This research proposes an interactive framework for prosumers by a market-based platform to utilize and trade flexibility. The suggested framework comprises a novel flexibility allocation...
Rapid authentication of intact saffron stigma thorough the package using Vis-SWNIR hyperspectral imaging coupled with chemometrics
, Article Journal of Food Composition and Analysis ; Volume 124 , 2023 ; 08891575 (ISSN) ; Hashemi Nasab, F. S ; Parastar, H ; Sharif University of Technology
Academic Press Inc
2023
Abstract
This study presents a rapid method for detecting and authenticating intact saffron stigma through its packaging using visible-short wavelength near-infrared (Vis-SWNIR) hyperspectral imaging (HSI) in conjunction with chemometrics. A dataset containing 38 authentic saffron samples was utilized, and HSI images were captured within the spectral range of 400–950 nm. Multivariate curve resolution-alternating least squares (MCR-ALS) was used to obtain pure spatial and spectral profiles of the components. The resolved spatial profiles were then subjected to principal component analysis (PCA) to identify potential patterns in the authentic samples. Binary mixtures of pooled saffron samples and...
Oxidation Desulfurization of Liquid Fuels Using TiO2-based Photocatalysts
, M.Sc. Thesis Sharif University of Technology ; Khorasheh, Farhad (Supervisor) ; Larimi, Afsaneh Sadat (Supervisor)
Abstract
Due to the increasing consumption of fuel, the use of new methods with high efficiency to remove sulfur from fossil fuels is felt more than ever. Hydrogenation and oxidation of sulfur organic matter, such as thiophenes, is an old method of desulfurization of liquid fuels. Using a photocatalyst, everything can be done in an environment that is very low cost. In this study, the photocatalytic elimination of dibenzothiophene was investigated. For this purpose, carbon-doped thiamine dioxide was used as the photocatalytic base, which is synthesized by hydrothermal method. This method is the same source of titanium and carbon. To increase the performance of the catalyst, platinum metal was loaded...
Unraveling Legal Complexities: Muslim and non-Muslim Estate Administration Process in Malaysia and Brunei
, Article De Jure: Jurnal Hukum dan Syar'iah ; Volume 16, Issue 2 , 2024 , Pages 531-554 ; 20851618 (ISSN) ; Alihan, A. A ; Hamid, A. A. A ; Sultan, B ; Sharif University of Technology
2024
Abstract
Estate administration involves managing and distributing a deceased individual’s assets to beneficiaries, as well as managing the liabilities. This process comprises legal, financial, and administrative tasks that ensure assets are transferred based on the deceased's wishes and in accordance with the law. In Southeast Asia countries such as Indonesia, Malaysia and Brunei where Muslims represents the majority of population, the Islamic law plays an integral part in the inheritance management as the process to be in line with the Islamic teachings and principle. The role of the syariah authority namely the syariah courts is prevalent and therefore, abidance to the rule under the syariah legal...
Intelligent semi-active vibration control of eleven degrees of freedom suspension system using magnetorheological dampers
, Article Journal of Mechanical Science and Technology ; Volume 26, Issue 2 , 2012 , Pages 323-334 ; 1738494X (ISSN) ; Sarrafan, A ; Khayyat, A. A. A ; Zabihollah, A ; Sharif University of Technology
2012
Abstract
A novel intelligent semi-active control system for an eleven degrees of freedom passenger car's suspension system using magnetorheological (MR) damper with neuro-fuzzy (NF) control strategy to enhance desired suspension performance is proposed. In comparison with earlier studies, an improvement in problem modeling is made. The proposed method consists of two parts: a fuzzy control strategy to establish an efficient controller to improve ride comfort and road handling (RCH) and an inverse mapping model to estimate the force needed for a semi-active damper. The fuzzy logic rules are extracted based on Sugeno inference engine. The inverse mapping model is based on an artificial neural network...
Performance and exhaust emission characteristics of a spark ignition engine operated with gasoline and CNG blend
, Article Proceedings of the Spring Technical Conference of the ASME Internal Combustion Engine Division ; 2012 , Pages 179-187 ; 15296598 (ISSN) ; 9780791844663 (ISBN) ; Hamidi, A. A ; Mozafari, A. A ; Sharif University of Technology
2012
Abstract
Using CNG as an additive for gasoline is a proper choice due to higher octane number of CNG enriched gasoline with respect to that of gasoline. As a result, it is possible to use gasoline with lower octane number in the engine. This would also mean the increase of compression ratio in SI engines resulting in higher performance and lower gasoline consumption. Over the years, the use of simulation codes to model the thermodynamic cycle of an internal combustion engine have developed tools for more efficient engine designs and fuel combustion. In this study, a thermodynamic cycle simulation of a conventional four-stroke spark-ignition engine has been developed. The model is used to study the...
A comparative study of the performance of a SI engine fuelled by natural gas as alternative fuel by thermodynamic simulation
, Article 2009 ASME Internal Combustion Engine Division Fall Technical Conference, ICEF 2009, Lucerne, 27 September 2009 through 30 September 2009 ; 2009 , Pages 49-57 ; 9780791843635 (ISBN) ; Hamidi, A. A ; Mozafari, A. A ; Sharif University of Technology
American Society of Mechanical Engineers (ASME)
2009
Abstract
With the declining energy resources and increase of pollutant emissions, a great deal of efforts has been focused on the development of alternatives for fossil fuels. One of the promising alternative fuels to gasoline in the internal combustion engine is natural gas [1-5]. The application of natural gas in current internal combustion engines is realistic due to its many benefits. The higher thermal efficiency due to the higher octane value and lower exhaust emissions including CO2 as a result of the lower carbon to hydrogen ratio of the fuel are the two important feature of using CNG as an alternative fuel. It is well known that computer simulation codes are valuable economically as a cost...
Analytical and experimental analyses of nonlinear vibrations in a rotary inverted pendulum
, Article Nonlinear Dynamics ; Volume 107, Issue 3 , 2022 , Pages 1887-1902 ; 0924090X (ISSN) ; Pasharavesh, A ; Khayyat, A. A. A ; Sharif University of Technology
Springer Science and Business Media B.V
2022
Abstract
Gaining insight into possible vibratory responses of dynamical systems around their stable equilibria is an essential step, which must be taken before their design and application. The results of such a study can significantly help prevent instability in closed-loop stabilized systems by avoiding the excitation of the system in the neighborhood of its resonance. This paper investigates nonlinear oscillations of a rotary inverted pendulum (RIP) with a full-state feedback controller. Lagrange’s equations are employed to derive an accurate 2-DoF mathematical model, whose parameter values are extracted by both the measurement and 3D modeling of the real system components. Although the governing...
A suction-controlled ring device to measure the coefficient of lateral soil pressure in unsaturated soils
, Article Geotechnical Testing Journal ; Volume 44, Issue 1 , 2020 ; Garakani, A. A ; Golshani, A ; Mirzaii, A ; Sharif University of Technology
ASTM International
2020
Abstract
A suction-controlled ring device has been developed to continuously measure the coefficient of lateral soil pressure in deformable unsaturated soil samples from the at-rest to the active condition under application of increasing vertical pressure and controlled matric suction. The device incorporates a thin aluminum specimen ring equipped with horizontal strain gages for recording the lateral soil strains. In addition, a sensor recording water volume changes is utilized to continuously monitor the degree of saturation of the soil sample during tests. The matric suction within the soil texture is controlled using the axis translation technique. In order to verify the performance of the ring...
Gum tragacanth gels as a new supporting matrix for immobilization of whole-cell
, Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 24, Issue 4 , 2005 , Pages 1-7 ; 10219986 (ISSN) ; Vaziri, A ; Seifkordi, A. A ; Kheirolomoom, A ; Sharif University of Technology
2005
Abstract
We introduce a new smooth, non-toxic, biocompatible method for cross-linking of gum tragacanth (GT), a polysaccharide of natural origin, in order to serve as a new supporting matrix for immobilization systems. The modified gum is used as a matrix for the catalysis of the conversion of benzyl penicillin to 6-aminopenicillanic acid (6-APA) by means of Escherichia coli ATCC11105 with penicillin G acylase (PGA) activity. The results show that GT beads can not only serve as a proper matrix for immobilization, but show enhanced hydrolysis rate and stability compared to other immobilization systems used for this reaction. This signifies the potential of GT as a biocompatible matrix for...
True Class-E Design For Inductive Coupling Wireless Power Transfer Applications
, Article 30th International Conference on Electrical Engineering, ICEE 2022, 17 May 2022 through 19 May 2022 ; 2022 , Pages 864-868 ; 9781665480871 (ISBN) ; Safarian, A ; Fotowat Ahmady, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
The Class-E power amplifier has been widely studied and formulated in the literature. Although the majority of reported inductive coupling wireless power transfer (WPT) systems use a class-E power amplifier for driving the primary coil, still there is a lack of a comprehensive study on class-E circuit dedicated to WPT, providing a set of closed form design equations for proper class-E operation. This paper presents the required design equations needed to design a 'true' class-E circuit for WPT applications. Equations for the series-tuned secondary coil WPT system are presented, as well as two different design procedures for the parallel-tuned secondary coil. The derived equations have been...
Crashworthiness determination of side doors and B pillar of a vehicle subjected to pole side impact
, Article Applied Mechanics and Materials ; Vol. 663, issue , 2014 , p. 552-556 ; Faieza, A. A ; Sahari, B. B ; Nuraini, A. A ; Halali, M ; Sharif University of Technology
2014
Abstract
Pole Side Impact Tes is one out of three crash tests described by Euro NCAP standard for star rating of a vehicle and is required for assessing the Adult Occupant Protection. In this paper the goal is to determine the crashworthiness of side doors and B pillar in a Pole Side Impact Test based on Euro New Car Assessment Program (Euro-NCAP) using computer and simulation method. In this matter, a vehicle model has been prepared and meshed using Hypermesh and CATIA. The velocity of 29 km/h has been assigned to the vehicle which was on top of a cart while the pole has been assigned as a rigid static object based on Euro NCAP requirements specifically. Results show that different amounts of energy...