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Synthesis and Characterization of Cu(II) Complexes with an Bidentate N,O-type Schiff Base Ligands and Study of the Catalytic Properties in Click Reactions
, M.Sc. Thesis Sharif University of Technology ; Bagherzadeh, Mojtaba (Supervisor)
Abstract
Two new copper(II) complexes, [CuL2] and [Cu(phox)2], were synthesized by reaction of 1-((4-bromophenylimino)methyl)naphthalen-2-ol, HL, and 2-(2′-hydroxyphenyl)-2-oxazoline, Hphox, as ligands and copper(II) acetate mono-hydrate with the ratio 2:1 (ligand:metal), respectively. For characterization and structure determination of synthesized complexes, different techniques were performed such as FT-IR, elemental analyses (CHN), and X-ray crystallography. The geometry around Cu atom is almost square planar in both complexes. The catalytic activity of the complexes was evaluated in azide–alkyne cycloaddition reaction in water without need of any additional agent. The reaction conditions for the...
On existence, non-existence and blow-up results for a singular semilinear laplacian problem
, Article European Journal of Mathematics ; Volume 3, Issue 1 , 2017 , Pages 150-170 ; 2199675X (ISSN) ; Hesaaraki, M ; Sharif University of Technology
2017
Abstract
We study the optimal value of p for solvability of the problem [Equation not available: see fulltext.]Here λ, α> 0 , p> 1 , f is a non-negative measurable function and [InlineEquation not available: see fulltext.], N⩾ 3 , is an open bounded domain with smooth boundary such that 0 ∈ Ω. We find the critical threshold exponent p+(λ, α) for solvability of (1) and show that if [InlineEquation not available: see fulltext.], 1 < p< p+(λ, α) and [InlineEquation not available: see fulltext.] for some sufficiently small c0> 0 , then there exists a solution as a limit of solutions to approximating problems. Moreover, for p⩾ p+(λ, α) we show that a complete blow-up phenomenon occurs. © 2017, Springer...
Preparation of Thin-Film Nanocomposite Membranes Based on Metal-Organic Frameworks (Mofs) and Study of their Performance in Forward Osmosis (Fo) Process
, Ph.D. Dissertation Sharif University of Technology ; Bagherzadeh, Mojtaba (Supervisor)
Abstract
The forward osmosis (FO) process is a high potential emerging membrane process in the seawater desalination and contaminated water treatment fields. One of the main challenges facing this process is the weak separation (high reverse solute flux, low water flux, and insufficient selectivity) and antifouling performances of its membranes. Various sections of this study focus on the development of FO membranes and their performance improvement. For this purpose, thin-film composite membranes with the same combination of polyethersulfone/polyamide (PES/PA) have been used to investigate the effect of metal-organic frameworks (MOFs) introduction on their performance. The support layer in all cases...
A novel 12-molybdovanadate nanocluster: synthesis, structure investigation and its application as an efficient heterogeneous sulfoxidation catalyst
, Article Inorganic Chemistry Communications ; Volume 83 , 2017 , Pages 103-108 ; 13877003 (ISSN) ; Sheykhi, A ; Naslhajian, H ; Bayrami, A ; Bagherzadeh, M ; Holynska, M ; Sharif University of Technology
2017
Abstract
Tetraethylammonium salt of a new keggin-type 12-molybdovanadate nanocluster, [(C2H5)4N]4[VMo12O40] (1) was synthesized via reaction between sodium tungstate, ammonium vanadate and tetraethylammonium bromide in acidic medium. Compound 1 was characterized by X-ray crystallography, FT-IR, UV–Vis and cyclic voltammetry and then applied as an efficient heterogeneous catalyst to oxidation of various organosulfides to sulfoxides with H2O2 at room temperature with 81–100% conversion and 60–99% selectivity. Nanocluster 1 was also shown to display excellent recyclability – it can be reused more than 10 times. © 2017 Elsevier B.V
Existence of a unique positive entropy solution to a singular fractional Laplacian
, Article Complex Variables and Elliptic Equations ; 2020 ; Hesaaraki, M ; Sharif University of Technology
Taylor and Francis Ltd
2020
Abstract
In this paper, we study the existence of a positive solution to the elliptic problem: (Formula presented.) Here (Formula presented.) (N>2s) is an open bounded domain with smooth boundary, (Formula presented.) and (Formula presented.). For (Formula presented.), we take advantage of the convexity of Ω. The operator (Formula presented.) indicates the restricted fractional Laplacian, and μ is a non-negative Radon measure as a source term. The assumptions on f and h will be precised later. Besides, we will discuss the notion of entropy solution and its uniqueness for some specific measures. © 2020, © 2020 Informa UK Limited, trading as Taylor & Francis Group
A fractional Laplacian problem with mixed singular nonlinearities and nonregular data
, Article Journal of Elliptic and Parabolic Equations ; Volume 7, Issue 2 , 2021 , Pages 787-814 ; 22969020 (ISSN) ; Hesaaraki, M ; Sharif University of Technology
Birkhauser
2021
Abstract
In this note, we study on the existence and uniqueness of a positive solution to the following doubly singular fractional problem: {(-Δ)su=K(x)uq+f(x)uγ+μinΩ,u>0inΩ,u=0in(RN\u03a9).Here Ω ⊂ RN (N> 2 s) is an open bounded domain with smooth boundary, s∈ (0 , 1) , q> 0 , γ> 0 , and K(x) is a positive Hölder continuous function in which behaves as dist (x, ∂Ω) -β near the boundary with 0 ≤ β< 2 s. Also, 0 ≤ f, μ∈ L1(Ω) , or non-negative bounded Radon measures in Ω. Moreover, we assume that 0<βs+q<1, or βs+q>1 with 2 β+ q(2 s- 1) < (2 s+ 1). For s∈(0,12), we take advantage of the convexity of Ω. For any γ> 0 , we will prove the existence of a positive weak (distributional) solution to the above...
Existence of a unique positive entropy solution to a singular fractional Laplacian
, Article Complex Variables and Elliptic Equations ; Volume 66, Issue 5 , 2021 , Pages 783-800 ; 17476933 (ISSN) ; Hesaaraki, M ; Sharif University of Technology
Taylor and Francis Ltd
2021
Abstract
In this paper, we study the existence of a positive solution to the elliptic problem: (Formula presented.) Here (Formula presented.) (N>2s) is an open bounded domain with smooth boundary, (Formula presented.) and (Formula presented.). For (Formula presented.), we take advantage of the convexity of Ω. The operator (Formula presented.) indicates the restricted fractional Laplacian, and μ is a non-negative Radon measure as a source term. The assumptions on f and h will be precised later. Besides, we will discuss the notion of entropy solution and its uniqueness for some specific measures. © 2020 Informa UK Limited, trading as Taylor & Francis Group
Semilinear Biharmonic Problem with a Singular Term
, M.Sc. Thesis Sharif University of Technology ; Hesaaraki, Mahmoud (Supervisor)
Abstract
The aim of this work is to study the optimal exponent p to have solvability of semilinear biharmonic problem with a singular term in a smooth and bounded domain such that contains origin in Euclidean space with dimension greater than 4. The singular term is related to the Hardy inequality. First of all, it is not difficult to show that any positive supersolution of problem is unbounded near the origin and then additional hypotheses on p are needed to ensure existence of solutions. We will say that problem blows up completely if the solutions to the truncated problems (with a bounded weight instead of the Hardy singularity) tend to infinity for every x in domain as n goes infinity. The main...
Selective oxidation of organosulfurs with a sandwich-type polyoxometalate/hydrogen peroxide system
, Article Polyhedron ; Volume 186 , 1 August , 2020 ; Amini, M ; Dastyar, M. A ; Bayrami, A ; Bagherzadeh, M ; Farnia, S. M. F ; Janczak, J ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
A dimeric tungstophosphate, Na14[Co4(PW9O35)2].28H2O (1), was synthesized via a simple one-pot method and characterized by single-crystal X-ray crystallography. Nanocluster 1 was exhibited to be able to selective oxidation of aliphatic and aromatic sulfides to sulfoxides in the presence of hydrogen peroxide at room temperature with high performance. Further investigations showed that this catalyst could reuse four times without a significant reduction in its activity for the oxidation of methyl phenyl sulfide. © 2020 Elsevier Ltd
Infinitely many solutions for a new class of Schrödinger–Kirchhoff type equations in RN involving the fractional p-Laplacian
, Article Journal of Elliptic and Parabolic Equations ; Volume 7, Issue 1 , 2021 , Pages 243-267 ; 22969020 (ISSN) ; Chung, N. T ; Bayrami Aminlouee, M ; Sharif University of Technology
Birkhauser
2021
Abstract
This paper deals with the existence of infinitely many solutions for a new class of Schrödinger–Kirchhoff type equations of the form M([u]s,pp+∫RNV(x)|u|pdx)[(-Δ)psu+V(x)|u|p-2u]=λh(x)|u|q-2u+f(x,u),x∈RN,where [u]s,pp:=∬R2N|u(x)-u(y)|p|x-y|N+spdxdy,s∈ (0 , 1) , N> sp, p≥ 2 , M(t) = a- btγ-1, t≥ 0 , 1<γ0 with a,b∈R0+:=[0,∞), λ is a parameter, q∈ (1 , p) , (-Δ)ps is the fractional p-Laplace operator, V: RN→ R+: = (0 , ∞) is a potential function, h is a sign-changing weight function and f is a continuous function satisfying the Ambrosetti–Rabinowitz condition or not. To our best knowledge, the results here are the first contributions to the study of fractional...
Global existence, blow-up and asymptotic behavior of solutions for a class of p(x)-Choquard diffusion equations in RN
, Article Journal of Mathematical Analysis and Applications ; Volume 506, Issue 2 , 2022 ; 0022247X (ISSN) ; Hamdani, M. K ; Bayrami Aminlouee, M ; Sharif University of Technology
Academic Press Inc
2022
Abstract
In this paper, we investigate the local and global existence, asymptotic behavior, and blow-up of solutions to the Cauchy problem for Choquard-type equations involving the p(x)-Laplacian operator. As a particular case, we study the following initial value problem [Formula presented] where p,q,V:RN→R and α:RN×RN→R are continuous functions that satisfy some conditions which will be stated later on, and u0:RN→R is the initial function. Under some appropriate conditions, we prove the local and global existence of solutions for the above Cauchy problem by employing the abstract Galerkin approximation. Moreover, the blow-up of solutions and large-time behavior are also investigated. © 2021...
Zwitterion-functionalized MIL-125-NH2-based thin-film nanocomposite forward osmosis membranes: towards improved performance for salt rejection and heavy metal removal
, Article New Journal of Chemistry ; Volume 46, Issue 31 , 2022 , Pages 15205-15218 ; 11440546 (ISSN) ; Bagherzadeh, M ; Navi, H ; Nikkhoo, M ; Amini, M ; Sharif University of Technology
Royal Society of Chemistry
2022
Abstract
In the current study, thin-film nanocomposite membranes (TFN-Mx) based on a zwitterion-functionalized metal-organic framework (MOF) have been developed for the forward osmosis (FO) salt-water separation process. The active polyamide layer was formed through the interfacial polymerization of the m-phenylenediamine aqueous phase (with or without the presence of MIL-125-NH-CC-Cys) and the trimesoyl chloride organic phase. In comparison with the results from the surface of the unmodified membrane, a nanofiller-incorporated TFN-M0.10 membrane represents a smoother and more wettable surface that collaborates synergically to enhance the membrane antifouling ability. Among the examined membranes,...
Oxido-peroxido W(VI)-histidine–MgAl-layered double hydroxide composite as an efficient catalyst in sulfide oxidation
, Article Applied Organometallic Chemistry ; Volume 32, Issue 6 , 2018 ; 02682605 (ISSN) ; Amini, M ; Morteza, S ; Farnia, F ; Bayrami, A ; Bagherzadeh, M ; Gautam, S ; Chae, K. H ; Sharif University of Technology
John Wiley and Sons Ltd
2018
Abstract
Oxido-peroxido W(VI)-histidine–MgAl-layered double hydroxide composite was prepared by using MgAl-layered double hydroxide as a host and oxido-peroxido W(VI)-histidine complex as a guest. The composite was characterized by XRD, IR, EDX,SEM and TEM techniques. This composite is tested for catalytic selective sulfoxidation reactions using hydrogen peroxide as oxidant showing good to moderate conversion along with high selectivity. Copyright © 2018 John Wiley & Sons, Ltd
Nonlocal Lazer–McKenna-type problem perturbed by the Hardy’s potential and its parabolic equivalence
, Article Boundary Value Problems ; Volume 2021, Issue 1 , 2021 ; 16872762 (ISSN) ; Hesaaraki, M ; Karim Hamdani, M ; Thanh Chung, N ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
In this paper, we study the effect of Hardy potential on the existence or nonexistence of solutions to the following fractional problem involving a singular nonlinearity: {(−Δ)su=λu|x|2s+μuγ+fin Ω,u>0in Ω,u=0in (RN∖Ω). Here 0 < s< 1 , λ> 0 , γ> 0 , and Ω ⊂ RN (N> 2 s) is a bounded smooth domain such that 0 ∈ Ω. Moreover, 0 ≤ μ, f∈ L1(Ω). For 0 < λ≤ Λ N,s, Λ N,s being the best constant in the fractional Hardy inequality, we find a necessary and sufficient condition for the existence of a positive weak solution to the problem with respect to the data μ and f. Also, for a regular datum of f, under suitable assumptions, we obtain some existence and uniqueness results and calculate the rate of...
Singular PDEs with Irregular Data
, Ph.D. Dissertation Sharif University of Technology ; Hesaaraki, Mahmoud (Supervisor) ; Fotouhi Firoozabad, Morteza (Co-Supervisor)
Abstract
Singular differential equations have a wide range of applications. Hardy singularities, which are connected to inequalities of the same name and have various extensions, are the most well-known singularities. The application of Hardy inequalities in quantum physics and also in the linearization of reaction-diffusion equations in thermodynamics and combustion theory motivates researchers to examine them. Singularities on a domain's boundary are another well-known type of singularity. In the study of fluid mechanics and pseudoplastic flows, these singularities emerge.Differential equations with coefficients or functions that are simply functions belonging to $ L^1 $, or bounded Radon measures,...
Thin-film nanocomposite membranes containing aspartic acid-modified MIL-53-NH2 (Al) for boosting desalination and anti-fouling performance
, Article Desalination ; Volume 521 , 2022 ; 00119164 (ISSN) ; Bagherzadeh, M ; Navi, H ; Chegeni, M ; Hosseinifard, M ; Amini, M ; Sharif University of Technology
Elsevier B.V
2022
Abstract
In the current study, the prospect improvements on desalination and anti-fouling performance of polyamide (PA)-based TFN membranes modified with MIL-53-NH-Asp have been investigated. MIL-53-NH2 nanoparticles (NPs) have been treated through a single-step post-synthesis modification reaction to enhance the hydrophilicity feature and compatibility with the PA layer. Various concentrations of synthesized NPs were dispersed in an aqueous phase consisting m-phenylenediamine and 2,6-diaminopyridine monomers for incorporation in the PA rejection layer. Analysis data of fabricated membranes provide evidence of changes in their physico-chemical properties after NPs incorporation. In comparison with...
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...