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    Introduction to the world of Quantum Computers

    , Article 5th IEEE International Conference on Cognitive Informatics, ICCI 2006, Beijing, 17 July 2006 through 19 July 2006 ; Volume 2 , 2006 , Pages 760-764 Jafarpour, S ; Sharif University of Technology
    2006
    Abstract
    The world is changing very fast, and so are the ways of communication and computation. This article is about a new communication and information technology based on the principles of the quantum physics. At first we discuss about some fundamental paradigms of Quantum Computers World, and then introducing the basis of quantum computation: "QBit". Afterthat we will explain some magic properties of this atomic QBit including Quantum Measurement, Superposition, Entanglement, etc. Then we introduce Quantum Gates the basic modules of the next generation computers. Their relation with the ordinary logical gates and the properties of some of the most useful quantum gates. And finally, we will have a... 

    Partially asymmetric simple exclusion model in the presence of an impurity on a ring

    , Article Journal of Physics A: Mathematical and General ; Volume 33, Issue 9 , 2000 , Pages 1797-1808 ; 03054470 (ISSN) Jafarpour, F. H ; Sharif University of Technology
    2000
    Abstract
    We study a generalized two-species model on a ring. The original model (Mallick K 1996 J. Phys. A: Math. Gen. 29 5375) describes ordinary particles hopping exclusively in one direction in the presence of an impurity. The impurity hops with a rate different from that of ordinary particles and can be overtaken by them. Here we let the ordinary particles also hop backward with rate q. Using the matrix product ansatz we obtain the relevant quadratic algebra. A finite-dimensional representation of this algebra enables us to compute the stationary bulk density of the ordinary particles, as well as the speed of impurity on a set of special surfaces of the parameter space. We will obtain the phase... 

    Exact solution of an exclusion model in the presence of a moving impurity on a ring

    , Article Journal of Physics A: Mathematical and General ; Volume 33, Issue 48 , 2000 , Pages 8673-8680 ; 03054470 (ISSN) Jafarpour, F. H ; Sharif University of Technology
    2000
    Abstract
    We study a recently introduced model by Arndt et al which consists of positive and negative particles on a ring. The positive (negative) particles hop clockwise (anticlockwise) with unit rate and oppositely charged particles may swap their positions with asymmetric rates q and unity. In this paper we assume that a finite density of positively charged particles ρ and only one negative particle (which plays the role of an impurity) exist on the ring. It turns out that the canonical partition function of this model can be calculated exactly using matrix product ansatz formalism. In the limit of infinite system size and infinite number of positive particles, we can also derive exact expressions... 

    Improved adsorption performance of ZIF-8 towards methylene blue dye by hybridization with nanodiamond

    , Article Journal of Water Process Engineering ; Volume 50 , 2022 ; 22147144 (ISSN) Mirzaei, K ; Mohammadi, A ; Jafarpour, E ; Shojaei, A ; Moghaddam, A. L ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    A series of ZIF-8/OND hybrid nanostructures with different percentages of oxidized nanodiamond (OND) was prepared. Then, the adsorptive removal performance of pristine ZIF-8 and its nanohybrids with OND towards methylene blue (MB) was investigated. The fabricated adsorbents were characterized via thermogravimetric analysis, X-ray diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption/desorption, field emission scanning electron microscopy and zeta potential measurements. The maximal adsorption capacity of ZIF-8 (242 mg/g) was found to grow steadily with the increment in OND content and reached an approximate plateau at 343 mg/g for the nanohybrid containing 5 wt% OND, i.e.... 

    An investigation on the influence of highly acidic media on the microstructural stability and dye adsorption performance of UiO-66

    , Article Applied Surface Science ; Volume 618 , 2023 ; 01694332 (ISSN) Mirzaei, K ; Jafarpour, E ; Shojaei, A ; Khasraghi, S. S ; Jafarpour, P ; Sharif University of Technology
    Elsevier B.V  2023
    Abstract
    Stability of UiO-66 in 1 M HCl for different exposure times up to 15 days was investigated by employing various characterization techniques such as XRD, FESEM, TEM, TGA, and nitrogen adsorption/desorption. The lower surface area, smaller pore size, and slightly lower thermal stability indicated that the UiO-66 structure experienced a partial breakdown, but could maintain its main structure and showed acceptable stability. In addition, the exposure to the HCl solution added to the missing-linker defects in the structure of UiO-66. The adsorptive performance of HCl-aged UiO-66 nanoparticles towards anionic methyl orange (MO) dye was then evaluated. Compared to as-synthesized UiO-66, maximum... 

    Effect of Carbon Nanoparticle Hybrid on the Properties of Styrene-Butadiene Rubber (SBR)

    , M.Sc. Thesis Sharif University of Technology Jafarpour, Erfan (Author) ; Shojaei, Akbar (Supervisor)
    Abstract
    Flexible polymers (elastomers) are especially suitable for dynamic applications, and carbon fillers are well-known filler for elastomers. These are widely used in elastomer matrices for various commercial applications. Some of carbon nano fillers like Nano Diamond cannot impart such high degree of reinforcement to polymer matrices mainly because of improper filler dispersion and lack of strong filler-polymer interaction. In this effort, we examine the effects of two different nanostructured carbons when they are incorporated in a rubber matric in terms of mechanical, thermal and electrical properties of the nanocomposites. Different ingredients and hybrid nanofillers were added to matric by... 

    High-performance styrene-butadiene rubber nanocomposites based on carbon nanotube/nanodiamond hybrid with synergistic thermal conduction characteristics and electrically insulating properties

    , Article Polymer ; Volume 196 , 20 May , 2020 Jafarpour, E ; Shojaei, A ; Ahmadijokani, F ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    Reinforcement of rubbery materials with carbon nanotube (CNT) has gained much attention over the last few decades due to the inherent ability of CNT to improve the physical and mechanical properties of polymer composites. However, CNT renders electrical conductivity to the rubber composites, which could be problematic for a number of applications. In an attempt to overcome such issues, we controlled the insulating properties of styrene-butadiene rubber (SBR) nanocomposites by hybridization of CNT with nanodiamond (ND) particles without scarifying desirable features of the nanoparticles. In this respect, the effects of carbon nanotube (CNT) and nanodiamond (ND), either individually or in... 

    Design of Low Power Harmonic Rejection Mixer for Wideband Application

    , M.Sc. Thesis Sharif University of Technology Jafarpour Dahaghani, Reza (Author) ; Akbar, Fatemeh (Supervisor)
    Abstract
    The increasing demand for communication bandwidth and limited spectrum availability have heightened the complexity of radio front-end circuits in IoT applications. Achieving spectral efficiency is a key challenge, particularly for IoT devices operating at specific frequency bands such as 315 MHz, 433 MHz, 868 MHz, and 915 MHz.Due to the limited linearity of the transmit path, harmonic distortion components, known as counter intermodulation (CIM) products, are generated. These CIM products can directly fall into the receiver (RX) band or enter it via cross-modulation, thereby degrading the frequency division performance. Additionally, CIM products can interfere with protected bands, violating... 

    Design and synthesis of AKAM: A RISC asynchronous microprocessor

    , Article 2007 International Conference on Intelligent and Advanced Systems, ICIAS 2007, Kuala Lumpur, 25 November 2007 through 28 November 2007 ; 2007 , Pages 1318-1323 ; 1424413559 (ISBN); 9781424413553 (ISBN) Mirza Aghatabar, M ; Rasooli, A ; Jafarpour, B ; Sharif University of Technology
    2007
    Abstract
    Asynchronous microprocessors are more flexible to adapt to physical parameters, and have lower power consumption than synchronous microprocessors. In this paper we will introduce the design of an asynchronous microprocessor (V8-uRISC) and explore its design process compared to synchronous design. The processor is synthesized by Persia, an automatic tool for synthesizing asynchronous circuits. We have performed full functional test at various levels of design and synthesis. Our results show that an area overhead is expected for the asynchronous design as the cost for lower power and more robustness. ©2007 IEEE  

    Performance optimization of polymeric porous membrane-based liquid desiccant air dehumidifier used in air conditioning system

    , Article International Journal of Energy and Environmental Engineering ; Volume 11, Issue 1 , December , 2020 , Pages 55-71 Jafarpour, A. M ; Fazelpour, F ; Mousavi, S. A ; Sharif University of Technology
    Springer  2020
    Abstract
    In this study an experimental design was developed to optimize the performance and structure of a membrane-based parallel-plate liquid desiccant dehumidifier used in air conditioning regeneration system which operates under high humidity weather conditions. We conducted a series of polymeric porous membranes with different compositions fabricated that were prepared with various weight percentages of polysulfone (PSU), mixed with N-methyl-2-pyrrolidone (NMP) and dimethyl form amide (DMF) solvents. Furthermore, the designed experiments were performed under various operating conditions, indicating that the dehumidification efficiency declines with increasing flow rate, temperature, and... 

    Simulator Development for Thermal Operation (Pre-heating) of SAGD Techniques

    , M.Sc. Thesis Sharif University of Technology Jafarpour, Mahshid (Author) ; Pishvaie, Mahmoud Reza (Supervisor) ; Bozorgmehri, Ramin (Supervisor)
    Abstract
    This work describes the use of a two-dimensional numerical simulator for Steam Assisted Gravity Drainage (SAGD) using the model proposed by Coats et al with some improvements. Despite the Coats model this developed model accounts for capillary and gravity effects in the energy equation with a variable thermal conductivity of the formation. First, a sensitivity analysis is performed for SAGD process. Then, the simulator is used to describe the pre-heating process preceding SAGD. We studied two methods of preheating process and found that there exists an optimum method of preheating for any reservoir. We concluded that longer preheating period does not necessarily yield a faster recovery  

    UV-prepared salep-based nanoporous hydrogel for controlled release of tetracycline hydrochloride in colon

    , Article Journal of Photochemistry and Photobiology B: Biology ; Volume 102, Issue 3 , March , 2011 , Pages 232-240 ; 10111344 (ISSN) Bardajee, G. R ; Pourjavadi, A ; Ghavami, S ; Soleyman, R ; Jafarpour, F ; Sharif University of Technology
    2011
    Abstract
    A highly swelling nanoporous hydrogel (NPH) was synthesized via UV-irradiation graft copolymerization of acrylic acid (AA) onto salep backbone and its application as a carrier matrix for colonic delivery of tetracycline hydrochloride (TH) was investigated. Optimized synthesis of the hydrogel was performed by the classic method. The swelling behavior of optimum hydrogel was measured in different media. The hydrogel formation was confirmed by Fourier transform infrared spectroscopy (FTIR) and thermo-gravimetric analysis (TGA/DTG/DTA). The study of the surface morphology of hydrogels using SEM showed a nanoporous (average pore size: about 350 nm) structure for the sample obtained under... 

    Photonic band structure of isotropic and anisotropic Abrikosov lattices in superconductors

    , Article Physica C: Superconductivity and its Applications ; Volume 467, Issue 1-2 , December , 2007 , Pages 51-58 ; 09214534 (ISSN) Zandi, H ; Kokabi, A ; Jafarpour, A ; Khorasani, S ; Fardmanesh, M ; Adibi, A ; Sharif University of Technology
    2007
    Abstract
    We have performed a numerical solution for band structure of an Abrikosov vortex lattice in type-II superconductors forming a periodic array in two dimensions for applications of incorporating the photonic crystals concept into superconducting materials with possibilities for optical electronics. The implemented numerical method is based on the extensive numerical solution of the Ginzburg-Landau equation for calculating the parameters of the two-fluid model and obtaining the band structure from the permittivity for both orthogonal polarizations, which depends on the above parameters and the frequency. This is while the characteristics of such crystals highly vary with an externally applied... 

    Photonic band structure of abrikosov lattices in superconductors

    , Article Photonic Crystal Materials and Devices VI, San Jose, CA, 22 January 2007 through 25 January 2007 ; Volume 6480 , 2007 ; 0277786X (ISSN) Zandi, H ; Kokabi, A ; Jafarpour, A. A ; Khorasani, S ; Fardmanesh, M ; Adibi, A ; Sharif University of Technology
    2007
    Abstract
    We have performed a numerical solution for band structure of an Abrikosov vortex lattice in type-11 superconductors forming a periodic array in two dimensions for applications of incorporating the photonic crystals concept into superconducting materials with possibilities for optical electronics. The implemented numerical method is based on the extensive numerical solution of the Ginzburg-Landau equation for calculating the parameters of the two-fluid model and obtaining the band structure from the permittivity, which depends on the above parameters and the frequency. This is while the characteristics of such crystals highly vary with an externally applied static normal magnetic field,... 

    Dose-dependent effects of nanoscale graphene oxide on reproduction capability of mammals

    , Article Carbon ; Volume 95 , December , 2015 , Pages 309-317 ; 00086223 (ISSN) Akhavan, O ; Ghaderi, E ; Hashemi, E ; Akbari, E ; Sharif University of Technology
    Elsevier Ltd  2015
    Abstract
    In vivo dose-dependent effects of nanoscale graphene oxide (NGO) sheets on reproduction capability of Balb/C mice were investigated. Biodistribution study of the NGO sheets (intravenously injected into male mice at dose of ∼2000 μg/mL or 4 mg/kg of body weight) showed a high graphene uptake in testis. Hence, in vivo effects of the NGO sheets on important characteristics of spermatozoa (including their viability, morphology, kinetics, DNA damage and chromosomal aberration) were evaluated. Significant in vivo effects was found at the injected concentrations ≥200 μg/mL after (e.g., ∼45% reduction in sperm viability and motility at 2000 μg/mL). Observation of remarkable DNA fragmentations and... 

    Accelerated differentiation of neural stem cells into neurons on ginseng-reduced graphene oxide sheets

    , Article Carbon ; Volume 66 , January , 2014 , Pages 395-406 Akhavan, O ; Ghaderi, E ; Abouei, E ; Hatamie, S ; Ghasemi, E ; Sharif University of Technology
    2014
    Abstract
    Asian red ginseng was used for green reduction of chemically exfoliated graphene oxide (GO) into reduced graphene oxide (rGO). The reduction level and electrical conductivity of the ginseng-rGO sheets were comparable to those of hydrazine-rGO ones. Reduction by ginseng resulted in repairing the sp 2 graphitic structure of the rGO, while hydrazine-rGO showed more defects and/or smaller aromatic domains. The ginseng-rGO sheets presented a better stability against aggregation than the hydrazine-rGO ones in an aqueous suspension. Whilst the hydrophobic hydrazine-rGO films exhibited no toxicity against human neural stem cells (hNSCs), the hydrophilic GO and ginseng-rGO films (as more... 

    Contested framings and policy controversies: Analysing biosafety policy-making in Iran

    , Article Science and Public Policy ; Volume 40, Issue 5 , 2013 , Pages 616-627 ; 03023427 (ISSN) Kashani, E. S ; Millstone, E ; Sharif University of Technology
    2013
    Abstract
    Vigorous debates have taken place within and between many countries about regulatory policy regimes covering the assessment and approval of genetically modified (GM) crops. In Iran, a very vigorous and hotly contested policy debate concerning legislation covering GM crops occurred between 2004 and 2009, but it was confined within government circles with almost no public discussion. This paper analyses the Iranian policy-making process in the period 2006-9. It explains how and why a stalemate arose in disputes between ministries and departments. The chosen analytical framework draws mainly on the regulation of technological risks and the analysis of public policy-making. It deploys the... 

    On the possible volumes of μ-way latin trades

    , Article Aequationes Mathematicae ; Volume 63, Issue 3 , 2002 , Pages 303-320 ; 00019054 (ISSN) Adams, P ; Billington, E. J ; Bryant, D. E ; Mahmoodian, E. S ; Sharif University of Technology
    Birkhauser Verlag Basel  2002
    Abstract
    A μ-way latin trade of volume s is a set of μ partial latin rectangles (of inconsequential size) containing exactly the same s filled cells, such that if cell (i, j) is filled, it contains a different entry in each of the μ partial latin rectangles, and such that row i in each of the μ partial latin rectangles contains, set-wise, the same symbols and column j, likewise. In this paper we show that all μ-way latin trades with sufficiently large volumes exist, and state some theorems on the non-existence of μ-way latin trades of certain volumes. We also find the set of possible volumes (that is, the volume spectrum) of μ-way latin trades for μ = 4 and 5. (The case μ = 2 was dealt with by Fu,... 

    The three-way intersection problem for latin squares

    , Article Discrete Mathematics ; Volume 243, Issue 1-3 , 2002 , Pages 1-19 ; 0012365X (ISSN) Adams, P ; Billington, E. J ; Bryant, D. E ; Mahmoodian, E. S ; Sharif University of Technology
    2002
    Abstract
    The set of integers k for which there exist three latin squares of order n having precisely k cells identical, with their remaining n2 -k cells different in all three latin squares, denoted by I3[n], is determined here for all orders n. In particular, it is shown that I3[n] = {0,.,n2 -15}U [n2 - 12,n2-9,n2], for n ≫8. ©2002 Eisevier Science B.V. All rights reserved  

    Integration of spatial fuzzy clustering with level set for segmentation of 2-D angiogram

    , Article IECBES 2014, Conference Proceedings - 2014 IEEE Conference on Biomedical Engineering and Sciences: "Miri, Where Engineering in Medicine and Biology and Humanity Meet", 8 December 2014 through 10 December 2014 ; December , 2015 , Pages 309-314 ; 9781479940844 (ISBN) Ghalehnovi, M ; Zahedi, E ; Fatemizadeh, E ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2015
    Abstract
    Coronary angiography is a vital instrument to detect the prevailing of vascular diseases, and accurate vascular segmentation acts a crucial role for proper quantitative analysis of the vascular tree morphological features. Level set methods are popular for segmenting the coronary arteries, but their performance is related to suitable start-up and optimum setting of regulating parameters, essentially done manually. This research presents a novel fuzzy level set procedure with the objective of segmentation of the coronary artery tree in 2-D X-ray angiography as automatically. It is clever to clearly develop from the early segmentation with spatial fuzzy grouping. The adjusting parameters of...