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    ChemInform abstract: microwave-assisted rapid ketalization/acetalization of aromatic aldehydes and ketones in aqueous media [electronic resource]

    , Article Journal of Chemical Research ; September 1999, Volume -, Number 9; Page(s) 562 to 563 Pourdjavadi, A. (Ali) ; Mirjalili, Bibi Fatemeh ; Sharif University of Technology
    Abstract
    Aromatic aldehydes and ketones are readily acetalized or ketalized under microwave irradiation in the presence of water as a solvent  

    Synthesis and characterization of poly(methacrylates) containing spiroacetal and norbornene moieties in side chain [electronic resource]

    , Article Journal of Applied Polymer Science ; Volume 77, Issue 1, pages 30–38, 5 July 2000 Pourdjavadi, A. (Ali) ; Mirjalili, Bibi Fatemeh ; Sharif University of Technology
    Abstract
    A four-step synthetic strategy was applied to achieve novel methacrylic monomers. 5-Norbornene-2,2-dimethanol was prepared from a Diels–Alder reaction of cyclopentadiene and acrolein, followed by the treatment of the adduct with an HCHO/KOH/MeOH solution. The resulting 1,3-diol (1) was then acetalized with different aromatic aldehydes having OH groups on the ring to produce four spiroacetal derivatives. The reaction of methacryloyl chloride with the phenolic derivatives led to four new methacrylic monomers that were identified spectrochemically (mass, FTIR, 1H-NMR, and 13C-NMR spectroscopy). Free radical solution polymerization was used to prepare novel spiroacetal–norbornene containing... 

    Silica chloride/wet SiO2 as a novel heterogeneous system for the deprotection of acetals under mild conditions

    , Article Phosphorus, Sulfur and Silicon and the Related Elements ; Volume 178, Issue 12 , 2003 , Pages 2667-2670 ; 10426507 (ISSN) Mirjalili, B. F ; Pourjavadi, A ; Zolfigol, M. A ; Bamoniri, A ; Sharif University of Technology
    Taylor and Francis Ltd  2003
    Abstract
    A combination of silica chloride and wet SiO2 was used as an effective deacetalizating agent for the conversion of acetals to their corresponding carbonyl derivatives under mild and heterogeneous condition  

    Nano-TiO2: An eco-friendly and re-usable catalyst for the synthesis of 14-aryl or alkyl-14H-dibenzo[a,j]xanthenes

    , Article Journal of the Iranian Chemical Society ; Volume 8, Issue SUPPL. 1 , February , 2011 , Pages S129-S134 ; 1735207X (ISSN) Mirjalili, B. F ; Bamoniri, A ; Akbari, A ; Taghavinia, N ; Sharif University of Technology
    2011
    Abstract
    Synthesis of 14-aryl or alkyl-14H-dibenzo[a,j]xanthenes using nano-TiO 2 as eco-friendly and efficient catalyst is reported. Short reaction times, high yields, a clean process, simple methodology, easy work-up and green conditions are advantages of this protocol  

    Online path planning for Surena III humanoid robot using model predictive control scheme

    , Article 4th RSI International Conference on Robotics and Mechatronics, ICRoM 2016, 26 October 2016 through 28 October 2016 ; 2017 , Pages 416-421 ; 9781509032228 (ISBN) Mirjalili, R ; Yousefi Koma, A ; Shirazi, F. A ; Mansouri, S ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2017
    Abstract
    In this paper, two online path planning methods are presented for SURENA III humanoid robot by using model predictive control scheme. The methods are general control schemes which can generate the online motions for walking of a humanoid robot. For lowering computational costs a three dimensional linear inverted pendulum model is used instead of the full dynamical model of the robot. The generated trajectories are then used for computing the zero-moment point (ZMP) of the robot and the joint torques. The resulted joint torques of the two methods are compared to torques obtained from Genetic Algorithm (GA) path planning method presented for SURENA III humanoid robot in previous studies. The... 

    Novel azo-containing polymethacrylates bearing spiroacetal-norbornene moiety and methylene spacers: synthesis and characterization [electronic resource]

    , Article European Polymer Journal ; Volume 37, Issue 10, October 2001, Pages 2111–2121 Pourdjavadi, A. (Ali) ; Mirjalili, Bibi Fatemeh ; Entezami, Ali A ; Zohuriaan-Mehr, Mohammad J ; Sharif University of Technology
    Abstract
    An eight-step synthetic strategy was followed to prepare a series of novel azobenzene-containing methacrylate monomers bearing spiroacetal-norbornene moiety and methylene spacers. Thus, the adduct 2, obtained from cyclopentadiene and acrolein, was converted to 1,3-diol 3. The diol was acetalized with nitrobenzaldehyde 4 under microwave irradiation to obtain nitro compound 5 that was then reduced to amino compound 6. Diazonium salt of 6 was coupled with phenol to produce phenolic compound 7 which was then reacted with n-dibromoalkanes (n=2, 4, 6, 8, 10) to yield bromo compounds 9a–e. Nucleophilic substitution reaction of the bromo compounds with lithium methacrylate produced the methacrylic... 

    Photovoltaic parameters and stability study of HTM-free mixed-cation perovskite solar cells by incorporating additives to absorbing layers

    , Article Journal of Materials Science: Materials in Electronics ; Volume 31, Issue 9 , 2020 , Pages 7123-7132 Doosthosseini, F ; Behjat, A ; Karimi Zarchi, A ; Taghavinia, N ; Mirjalili, B. F ; Sharif University of Technology
    Springer  2020
    Abstract
    In this study, quick route-coating is practiced to substitute methyl ammonium (MA) cation with formamidinium (FA) at different ratios. Through optimizing the MA:FA ratio, a maximum power conversion efficiency (PCE) of 8.31% is achieved for holes transporting material-free MA0.8FA0.2PbI3 mixed PSCs with the JSC of 19.02 mA/cm2, VOC of 0.859 V and FF of 50.88%. Then, to improve the performance, stability and carrier transport dynamic, various additives (PVA, PVP, PEG and EC) are incorporated into the perovskite layer. The treatment of perovskites with additives has proved to cause significant changes in the surface roughness, charge accumulation, charge transport, charge transport resistance,... 

    Novel azo-containing polymethacrylates bearing spiroacetal-norbornene moiety and methylene spacers: Synthesis and characterization

    , Article European Polymer Journal ; Volume 37, Issue 10 , 2001 , Pages 2111-2121 ; 00143057 (ISSN) Pourjavadi, A ; Fatemeh Mirjalili, B ; Entezami, A. A ; Zohuriaan Mehr, M. J ; Sharif University of Technology
    2001
    Abstract
    An eight-step synthetic strategy was followed to prepare a series of novel azobenzene-containing methacrylate monomers bearing spiroacetal-norbornene moiety and methylene spacers. Thus, the adduct 2, obtained from cyclopentadiene and acrolein, was converted to 1,3-diol 3. The diol was acetalized with nitrobenzaldehyde 4 under microwave irradiation to obtain nitro compound 5 that was then reduced to amino compound 6. Diazonium salt of 6 was coupled with phenol to produce phenolic compound 7 which was then reacted with n-dibromoalkanes (n = 2, 4, 6, 8, 10) to yield bromo compounds 9a-e. Nucleophilic substitution reaction of the bromo compounds with lithium methacrylate produced the methacrylic... 

    Developing a Parallel DSMC Algorithm for Simulating Flow in Micro-Nano Propulsion Systems

    , M.Sc. Thesis Sharif University of Technology Mirjalili, Vahid (Author) ; Darbandi, Masoud (Supervisor)
    Abstract
    With the rapid development of mico-nano propulsion systems in micro-spacecrafts and micro-sattelites, precise investigation of flow field in these devices has become necessary. Micro propulsion systems usually have a thrust in order of mili Newton, and they can be used for maneuvers of spacecrafts with mass of less than 10 kg. Micro propulsion systems are usually classified according to their thrust generation mechanism to different classes like cold gas, and chemical propulsion systems. Cold gas micro propulsion systems obtain their energy from thermodynamic expansion of gas and not by combustion. If the flow fiel dimensionare comparable to mean free path, rarefaction effects are observed... 

    Estimating Time and Cost Completion using Resource Performance

    , M.Sc. Thesis Sharif University of Technology Mirjalili, Reza (Author) ; Shadrokh, Sharam (Supervisor)
    Abstract
    Deciding for the future is one of the key tasks that project managers must carry out. Accurate Estimate at Completion helps them make the right decision. Numeruse novel methods have been proposed for calculation of estimate at completion which most of them are based on Earned Value Management. The question is whether considering the resources, as the essential elements of activities and therefoe the project, would result in a more accurate Estimation. In this Thesis, we propose a method that uses resource performance and activity structure to calculate the Estimate at Completion. The method also forecasts future resource usage. To evaluate the proposed method, we generated fictitious... 

    Numerical investigation of transient thermo-fluid processes in a Ranque-Hilsch vortex tube

    , Article International Journal of Refrigeration ; Volume 131 , 2021 , Pages 746-755 ; 01407007 (ISSN) Mirjalili, M ; Ghorbanian, K ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    A 2D numerical investigation is performed to better understand the transient thermo-fluid processes in a vortex tube for a cold mass fraction equal to0.44. The results along the Ranque-Hilsch vortex tube reveal a close agreement with past numerical and experimental data. The distribution of axial, radial, and tangential velocities as well as the stagnation pressure and temperature are examined at different positions for different time steps. The results indicate that the tangential velocity is the most significant velocity component and dominates the heat transfer and energy conversion processes. In addition, it is evident that the core of the cold end experiences the highest pressure... 

    Microstructural evolution and mechanical properties of friction stir welded AA2017 with different initial microstructures

    , Article Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications ; Vol. 228, issue. 1 , 2014 , p. 34-44 Mirjalili, A ; Jamshidi Aval, H ; Serajzadeh, S ; Kokabi, A. H ; Sharif University of Technology
    2014
    Abstract
    Residual stresses, local mechanical properties, and microstructural evolution in terms of grain structures and precipitation distribution have been studied in friction stir welding of AA2017 in T4 and T6 conditions. Microstructural studies including optical and electron microscopy were made to characterize the developed microstructures in different zones of the weldment. Furthermore, X-ray diffraction technique and digital image correlation technique were also utilized to assess residual stress and mechanical properties of the welded alloy. The results show that coarsening of semi-coherent plate-shaped precipitates and formation of incoherent spherical-shaped particles occur in heat affected... 

    Modeling and experimental study on friction stir welding of artificially aged AA2017 plates

    , Article Materials and Manufacturing Processes ; Volume 28, Issue 6 , 2013 , Pages 683-688 ; 10426914 (ISSN) Mirjalili, A ; Serajzadeh, S ; Jamshidi Aval, H ; Kokabi, A. H ; Sharif University of Technology
    2013
    Abstract
    Thermo-mechanical responses, developed microstructure, and mechanical properties in friction stir welding (FSW) of artificially aged AA2017 plates were investigated. A finite element analysis was first employed to evaluate hot deformation behavior of the alloy during welding. Also, hardness, yield strength, and microstructure of the welded alloy were examined using the results of the model and experimental testing. It was found that strain and temperature fields during welding are asymmetrically distributed and the maximum temperature locates in advancing side. Furthermore, considerable grain refinement is observed in the stir zone where recrystallized grains in the range of 3 to 8 m are... 

    Optimisation of a microwave-assisted method for extracting withaferin A from Withania somnifera Dunal. using central composite design

    , Article Phytochemical Analysis ; Volume 21, Issue 6 , 2010 , Pages 544-549 ; 09580344 (ISSN) Mirzajani, F ; Ghassempour, A ; Jalali-Heravi, M ; Mirjalili, M. H ; Sharif University of Technology
    2010
    Abstract
    Introduction - Recently, there have been growing attention on the modification and optimisation of new extraction and quantification methods, caused by the lack of environmentally friendly methodologies for the extraction of phytochemicals from complex matrices. In the case of pharmaceutical compounds, not only the extraction procedure but also the analysis method should be efficient, precise, fast and easy.Objectives - The essential pharmaceutical characteristics and trace concentration of withanolides led us to modify and optimise the previously reported extraction and quantification procedure for withaferin A (WA) as a candidate for withanolides.Matrial and methods - The WA from the... 

    Comparison Of Operation Of Metal Dampers In Steel Structures Based On Endurance Time Method

    , M.Sc. Thesis Sharif University of Technology Mirjalili, Amir (Author) ; Esmaeil Pourestekanchi, Homayun (Supervisor)
    Abstract
    Based on special properties of metal dampers such as high energy dissipation, stable hysteric cycles and simple application, low cost, insensitivity to changes of temperature and ability to be substituted after occurring of earthquakes, they are being used for structures control. ADAS and SSD are two kinds of metal dampers which are connected to top of the chevron braces and under the middle of beams. When shear forces are applied, these dampers yield and enter the plastic zone. In Endurance Time (ET) method gradually intensifying acceleration functions are created in a manner that the linear and nonlinear response spectra of them, while being proportional to average of real earthquakes... 

    Operation of tapered steel slit dampers in steel structures using the endurance time method

    , Article Civil-Comp Proceedings ; 2013 , Volume 102 ; 17593433 (ISSN) ; 9781905088577 (ISBN) Mirjalili, A ; Estekanchi, H.E ; Fakhri, M ; Sharif University of Technology
    Civil-Comp Press  2013
    Abstract
    Based on special properties of metal dampers such as high energy dissipation, stable hysteric cycles, simple application, low cost, insensitivity to changes of temperature and the ability to substitute after the occurrence of earthquakes, they are being used for structural control. One of these metal dampers which has been of special interest is the tapered steel slit damper (TSS). When shear forces are applied, this damper yields and enters the plastic zone. The TSS damper is made of pieces of standard wide flanges where slits have been extracted from their web. These dampers are connected to the top of the chevron braces and under the middle of the beams. In the endurance time (ET) method... 

    Direct simulation Monte Carlo solution of subsonic flow through micro/nanoscale channels

    , Article Journal of Heat Transfer ; Volume 131, Issue 9 , 2009 , Pages 1-8 ; 00221481 (ISSN) Roohi, E ; Darbandi, M ; Mirjalili, V ; Sharif University of Technology
    2009
    Abstract
    We use a direct simulation Monte Carlo (DSMC) method to simulate gas heating/cooling and choked subsonic flows in micro/nanoscale channels subject to either constant wall temperature or constant/variable heat flux boundary conditions. We show the effects of applying various boundary conditions on the mass flow rate and the flow parameters. We also show that it is necessary to add a buffer zone at the end of the channel if we wish to simulate more realistic conditions at the channel outlet. We also discuss why applying equilibrium-based Maxwellian distribution on molecules coming from the channel outlet, where the flow is nonequilibrium, will not disturb the DSMC solution. The current... 

    The modified dynamic-based pushover analysis of steel moment resisting frames

    , Article Structural Design of Tall and Special Buildings ; Volume 26, Issue 12 , 2017 ; 15417794 (ISSN) Mirjalili, M. R ; Rahimzadeh Rofooei, F ; Sharif University of Technology
    2017
    Abstract
    A modified dynamic-based pushover (MDP) analysis is proposed to properly consider the effects of higher modes and the nonlinear behavior of the structural systems. For this purpose, first, a dynamic-based story force distribution (DSFD) load pattern is constructed using a linear dynamic analysis, either time history (THA) or response spectrum (RSA). Performing an initial pushover analysis with the DSFD load pattern, a nonlinearity modification factor (NMF) is calculated to modify the DSFD load pattern. The envelope of the peak responses of the structure obtained from 2 pushover analyses with the modified DSFD load pattern as well as the code suggested first mode load pattern are considered... 

    Numerical Investigation of Nitrogen Condensation in a Two-phase Vortex Tube

    , M.Sc. Thesis Sharif University of Technology Mirjalili, Mohamad Reza (Author) ; Ghorbanian, Kaveh (Supervisor)
    Abstract
    The Ranque-Hilsch vortex tube (RHVT) has no moving parts through which a high-pressure fluid gains on rotational velocity by passing radially through the inlet nozzles and then enters the vortex chamber. Subsequently, the high-pressure fluid becomes divided into two relatively distinctive hot and cold axial flows. Today, while RHVT is of great industrial interest due to its simplicity in manufacturing and operation; however, the mechanism of energy dissociation, which is dominated by the complex coupled interaction of the viscous thermo-fluid characteristics and geometrical properties, is not fully understood and no clear theory has been proposed to explain the energy dissociation so far.... 

    Silica chloride/wet SiO2 as a novel heterogeneous system for the deprotection of acetals under mild conditions [electronic resource]

    , Article Phosphorus, Sulfur, and Silicon and the Related Elements ; Volume 178:2667-2670, Issue 12, 2003 Mirjalili, B. F. (BiBi Fatemeh) ; Pourjavadi, Ali ; Zolfigol, Mohammad Ali ; Bamoniri, Abdolhamid
    Abstract
    A combination of silica chloride and wet SiO2 was used as an effective deacetalizating agent for the conversion of acetals to their corresponding carbonyl derivatives under mild and heterogeneous condition