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    Inducing high exo selectivity in Diels–Alder reaction by dimethylborane substituent: a DFT study

    , Article Scientific Reports ; Volume 12, Issue 1 , 2022 ; 20452322 (ISSN) Taherinia, D ; Fattahi, A ; Sharif University of Technology
    Nature Research  2022
    Abstract
    In this work, the role of Lewis acid–base (LAB) interaction on the stereoselectivity of the Diels–Alder (DA) reaction has been studied by DFT in gas and solution (dichloromethane) phases. The calculations were performed at the B3LYP/6-311G++ (d, p) level. Two different series of DA reactions were investigated: (1)—three mono-substituted cyclopentadienes + dimethyl(vinyl)borane; (2)—five α,β-unsaturated carbonyl compounds + cyclopenta-2,4-dien-1-yldimethylborane. The reacting diene and dienophile pairs were chosen to restrict LAB interaction to the exo reaction pathway. It was found that in some of the examined cases, the favorable LAB interaction is so strong that it can lead to a completely... 

    A two-step watermarking attack using long-range correlation image restoration

    , Article Security and Communication Networks ; Volume 5, Issue 6 , AUG , 2012 , Pages 625-635 ; 19390122 (ISSN) Taherinia, A. H ; Jamzad, M ; Sharif University of Technology
    2012
    Abstract
    This paper presents an efficient scheme for blind watermark attacking using the concept of matching of the long-range data. The main idea of the proposed attack is to add plenty of noise to the watermarked image and then try to restore an unwatermarked copy of the noisy image. The aim is to destroy the watermark information without accessing the parameters used during the watermark embedding process. So, it allows our approach to be completely free from any pre-assumption on the watermarking algorithm or any other parameters that is used during the watermark embedding procedure. Experimental results show the proposed algorithm's superiority over several other traditional watermarking... 

    Blind dewatermarking method based on wavelet transform

    , Article Optical Engineering ; Volume 50, Issue 5 , 2011 ; 00913286 (ISSN) Taherinia, A. H ; Jamzad, M ; Sharif University of Technology
    2011
    Abstract
    Along with the improvement of image watermarking techniques, the necessity for effectively and comprehensively evaluating various algorithms becomes imperative. In this paper, we first propose a new categorization that fits for most of the existing watermarking algorithms that work in the wavelet domain. Then an adaptive watermarking attack for evaluating the robustness of watermarking schemes that are based on the proposed categorization is presented. This attack determines the flat regions, edges, and textures of the watermarked image and based on known features of each region the proposed attack tries to destroy the watermark information. This is done by separately manipulating the... 

    EWA: An exemplar-based watermarking attack

    , Article 2011 International Conference on Information Technology and Multimedia: "Ubiquitous ICT for Sustainable and Green Living", ICIM 2011, 14 November 2011 through 16 November 2011 ; Nov , 2011 , Page(s): 1 - 5 ; 9781457709890 (ISBN) Taherinia, A. H ; Jamzad, M ; Sharif University of Technology
    2011
    Abstract
    In this paper, we used image inpainting as a means for reconstruction of small damaged portions of a watermarked image so that the hidden watermark is not detectable afterwards. Our new watermarking attack algorithm extends the exemplar-based inpainting method, and then we apply it to intended noisy watermarked images to alter the watermark detection process. Our approach is completely free from any pre-assumption on the watermarking algorithm or any other parameters that is used during the watermark embedding procedure. The average PSNR/SSIM of the watermarked image after applying the proposed attack is more than 35/0.98 and the average NC for extracted watermark is lowers than 0.5, so... 

    A new spread spectrum watermarking method using two levels DCT

    , Article International Journal of Electronic Security and Digital Forensics ; Volume 3, Issue 1 , 2010 , Pages 1-26 ; 1751911X (ISSN) Taherinia, A. H ; Jamzad, M ; Sharif University of Technology
    2010
    Abstract
    In this paper, a discrete cosine transform (DCT) based blind watermarking scheme based on spread spectrum communications is proposed. We perform block-based DCT (BDCT) on the host image; then using the DC coefficients of each block, we construct a low-resolution approximation image. We apply BDCT on this approximation image, then watermark is embedded by adding a pseudo random noise sequence into its high frequencies. In detection stage, we extract the approximation image from the watermarked image, then the same pseudo random noise sequence is generated, and its correlation is computed with high frequencies of the watermarked approximation image. In our method, higher robustness is obtained... 

    A new adaptive watermarking attack in wavelet domain

    , Article 2009 International Multimedia, Signal Processing and Communication Technologies, IMPACT 2009, Aligarh, 14 March 2009 through 16 March 2009 ; 2009 , Pages 320-323 ; 9781424436040 (ISBN) Taherinia, A. H ; Jamzad, M ; Sharif University of Technology
    2009
    Abstract
    In this paper, we proposed a categorization for most of the existing watermarking algorithms that work in wavelet domain. Then an adaptive watermarking attack for digital images that is based on the proposed categorization is presented. This attack determines the flat regions, edges and textures of the watermarked image and based on known features of each region the proposed attack tries to destroy the watermark information by manipulating the wavelet coefficients of each region separately such that the least visual distortion will be imposed on the attacked image. We have tested the proposed method to attack two recent and robust watermarking methods and the results sound impressive. The... 

    A new watermarking attack based on content-aware image resizing

    , Article 2009 International Multimedia, Signal Processing and Communication Technologies, IMPACT 2009, Aligarh, 14 March 2009 through 16 March 2009 ; 2009 , Pages 177-180 ; 9781424436040 (ISBN) Taherinia, A. H ; Jamzad, M ; Sharif University of Technology
    2009
    Abstract
    In this paper, we propose a new method for damaging and destroying robust invisible watermarks using an image resizing technique which is named seam carving. By using this method we are able to resize watermarked images in a content-aware manner so that the synchronization of the embedder and extractor of watermarking system is broken and the watermark detection becomes impossible. In contrast to the available benchmarks like Stirmark, proposed attack does not severely reduce the quality of the watermarked image. Therefore it maintains the commercial value of the watermarked image. We have tested the proposed method to attack 3 recent and robust watermarking methods and the results sound... 

    A robust spread spectrum watermarking method using two levels DCT

    , Article International Journal of Electronic Security and Digital Forensics ; Volume 2, Issue 3 , 2009 , Pages 280-305 ; 1751911X (ISSN) Taherinia, A. H ; Jamzad, M ; Sharif University of Technology
    2009
    Abstract
    In this paper, a DCT-based blind watermarking scheme based on spread spectrum communications is proposed. We perform block-based DCT on the host image; then using the DC coefficients of each block, we construct a low-resolution approximation image. We apply block-based DCT on this approximation image, then watermark is embedded by adding a pseudo random noise sequence into its high frequencies. In detection stage, we extract the approximation image from the watermarked image, then the same pseudo random noise sequence is generated, and its correlation is computed with high frequencies of the watermarked approximation image. In our method, higher robustness is obtained because of embedding... 

    A robust image watermarking using two level DCT and wavelet packets denoising

    , Article International Conference on Availability, Reliability and Security, ARES 2009, Fukuoka, Fukuoka Prefecture, 16 March 2009 through 19 March 2009 ; 2009 , Pages 150-157 ; 9780769535647 (ISBN) Taherinia, A. H ; Jamzad, M ; Sharif University of Technology
    2009
    Abstract
    In this paper we present a blind low frequency watermarking scheme on gray level images, which is based on DCT transform and spread spectrum communications technique. We compute the DCT of non overlapping 8x8 blocks of the host image, then using the DC coefficients of each block we construct a low-resolution approximation image. We apply block based DCT on this approximation image, then a pseudo random noise sequence is added into its high frequencies. For detection, we extract the approximation image from the watermarked image, then the same pseudo random noise sequence is generated, and its correlation is computed with high frequencies of the watermarked approximation image. In our method,... 

    Trimetallic Co-Ni-Mn metal-organic framework as an efficient electrocatalyst for alkaline oxygen evolution reaction

    , Article Journal of Electroanalytical Chemistry ; Volume 922 , 2022 ; 15726657 (ISSN) Taherinia, D ; Hatami, H ; Mirzaee Valadi, F ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    Designing efficient and inexpensive catalysts toward the oxygen evolution reaction (OER) is vital for achieving sustainable and green hydrogen fuel production through water electrolysis. Herein, we have synthesized several bi- and trimetallic metal–organic frameworks (MOFs) composed of Co, Ni, and Mn metals and benzene-1,3,5-tricarboxylic acid linker. The MOFs were prepared via a simple hydrothermal method, and their electrocatalytic performances in alkaline OER were investigated. A battery of analytical techniques was employed to characterize the as-synthesized materials, including field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM),... 

    Efficiency assessment of job-level dynamic scheduling algorithms on identical multiprocessors

    , Article WSEAS Transactions on Computers ; Volume 5, Issue 12 , 2006 , Pages 2948-2955 ; 11092750 (ISSN) Salmani, V ; Naghibzadeh, M ; Taherinia, A. H ; Bahekmat, M ; Khajouie Nejad, S ; Sharif University of Technology
    2006
    Abstract
    This paper presents a comprehensive comparison between job-level dynamic scheduling algorithms on real-time multiprocessor environments using simulation. Earliest Deadline First (EDF) and Least Laxity First (LLF) are two well-known and extensively applied dynamic scheduling algorithms which have been proved to be optimal on uniprocessor systems. However, neither is shown to be optimal on multiprocessors. Many researches have already been done on aforementioned algorithms, but to the best of our knowledge, none of which has compared the efficiency of the two algorithms under similar conditions. Perhaps the main reason is that LLF algorithm is fully dynamic and impractical to implement. In... 

    Theoretical investigation of the effect of hydrogen bonding on the stereoselectivity of the Diels-Alder reaction

    , Article New Journal of Chemistry ; Volume 45, Issue 36 , 2021 , Pages 16760-16772 ; 11440546 (ISSN) Taherinia, D ; Mahmoodi, M. M ; Fattahi, A ; Sharif University of Technology
    Royal Society of Chemistry  2021
    Abstract
    In this article, we report the computational examination of the impact of hydrogen bonding (HB) on the stereoselectivity of a series of Diels-Alder (DA) reactions. Four different types of diene/dienophile couples were studied including (a) cyclopenta-2,4-dien-1-ol and heteroatom-substituted cyclopentenes, (b) substituted cyclopentadienes andN-protonated 2,5-dihydro-1H-pyrrole, (c) furan andN-protonated 5-azabicyclo[2.1.1]hex-2-ene, and (d)N-protonated cyclopenta-2,4-dien-1-amine and α,β-unsaturated carbonyl compounds. These systems were designed such that the HB can only exist in theexoreaction pathway. The optimized structures of the transition states (TSs) and products, along with the... 

    Investigation of the interfacial electron transfer kinetics in ferrocene-terminated oligophenyleneimine self-assembled monolayers

    , Article Langmuir ; Volume 36, Issue 42 , 2020 , Pages 12572-12579 Taherinia, D ; Sharif University of Technology
    American Chemical Society  2020
    Abstract
    In this article, the synthesis, characterization, and cyclic voltammetry (CV) measurements are reported for ferrocene-terminated oligophenyleneimine (OPI_Fc) and ferrocene-terminated conjugation-broken oligophenyleneimine (CB-OPI_Fc) self-assembled monolayers (SAMs) in two different electrolytes, namely, 1-ethyl-3-methylimidazolium-bis (trifluoromethyl-sulfonyl) imide (EMITFSI) ionic liquid and tetrabutylammonium hexafluorophosphate (Bu4NPF6) in acetonitrile (0.1 M solution). The SAMs were synthesized on Au surfaces by the sequential imine condensation reactions. CV was used to investigate the kinetics of electron transfer (ET) to the ferrocene, and it was observed that the standard ET rate... 

    Metal-organic framework derived NiSe2/CeO2nanocomposite as a high-performance electrocatalyst for oxygen evolution reaction (OER)

    , Article Sustainable Energy and Fuels ; Volume 5, Issue 11 , 2021 , Pages 2994-3000 ; 23984902 (ISSN) Taherinia, D ; Moravvej, S. H ; Moazzeni, M ; Akbarzadeh, E ; Sharif University of Technology
    Royal Society of Chemistry  2021
    Abstract
    The development of efficient and cost-effective catalysts for the oxygen evolution reaction is highly desirable for applications that are based on sustainable and clean technologies. In this study, we report the synthesis of a series of cerium(iv) oxide and nickel diselenide nanocomposites (NiSe2/CeO2) as efficient electrocatalysts for the oxygen evolution reaction in an alkaline medium. The ratios of the two substances were optimized to reach the highest catalytic activity. The structure and morphology of synthesized materials were investigated by XRD, FE-SEM, EDX, BET, XPS, and TEM techniques. It was observed that the nanocomposite with a 10 : 1 mass ratio of NiSe2to CeO2showed the best... 

    NiSe2Nanoparticles supported on halloysite sheets as an efficient electrocatalyst toward alkaline oxygen evolution reaction

    , Article Energy and Fuels ; Volume 36, Issue 23 , 2022 , Pages 14331-14340 ; 08870624 (ISSN) Taherinia, D ; Hatami, H ; Mirzaee Valadi, F ; Akbarzadeh, E ; Sharif University of Technology
    American Chemical Society  2022
    Abstract
    The oxygen evolution reaction (OER) with its sluggish kinetics has imposed a significant barrier to the sustainable and green generation of hydrogen fuel (via electrolysis of water) and the development of metal-air batteries. In this study, we report an efficient and novel OER electrocatalyst based on NiSe2nanoparticles (NPs) and the naturally abundant halloysite clay mineral. The NiSe2/halloysite nanocomposite (NiSe2/H) was prepared by a simple one-step hydrothermal route. The electrocatalytic performance of the as-synthesized nanocomposite and its components (pristine NiSe2and halloysite) toward OER in 1.0 KOH solution was examined. The NiSe2/H nanocomposite exhibited a significantly... 

    Induced soap-film flow by non-uniform alternating electric field

    , Article Journal of Electrostatics ; Volume 73 , February , 2015 , Pages 112-116 ; 03043886 (ISSN) Shirsavar, R ; Ramos, A ; Amjadi, A ; Taherinia, J ; Mashhadi, M ; Nejati, A ; Sharif University of Technology
    Elsevier  2015
    Abstract
    Fluid flows generated on soap films by non-uniform alternating electric fields are studied. Two parallel metal rods subjected to an AC voltage are placed perpendicular to the soap film, which is anchored in a dielectric frame. The fluid flow is generated by electrohydrodynamic induction. At very low signal frequencies there is induced surface charge, but there is no tangential electric field at the surface, so there is no force and no flow. Fluid flow is observed increasing the frequency, when there are both surface charge and tangential electric field. The flow velocity increases with decreasing thickness of the soap film  

    Nanosized NiFeSe2/NiCo2O4 hierarchical arrays on Ni foam as an advanced electrocatalyst for hydrogen generation

    , Article Sustainable Energy and Fuels ; Volume 7, Issue 1 , 2022 , Pages 112-121 ; 23984902 (ISSN) Tasviri, M ; Shekarabi, S ; Taherinia, D ; Zare Pour, M. A ; Sharif University of Technology
    Royal Society of Chemistry  2022
    Abstract
    The rational design of composite catalysts is critically essential for electrochemical water splitting. Here, we report on a novel hierarchical composite that comprises NiFeSe2 nanoparticles and NiCo2O4 nanoflakes supported on nickel foam (NF) as an efficient electrocatalyst for the hydrogen evolution reaction (HER). The conjunction of the NiFeSe2 nanoparticles and NiCo2O4 nanoflakes introduces a new synergistic effect for the HER, resulting in an improved NiCo2O4 catalyst. The as-prepared NiFeSe2/NiCo2O4/NF electrode exhibited an enhanced HER activity, with a low overpotential of 83 mV at a current density of 10 mA cm−2, a low Tafel slope of 45 mV dec−1, and an excellent long-term... 

    Investigation of the Effect of Various Electrolyte Additives to Increase the Overpotential of the Hydrogen and Oxygen Evolution Reactions in Lead-Acid Batteries

    , M.Sc. Thesis Sharif University of Technology Mohammadvand, Ali (Author) ; Taherinia, Davood (Supervisor)
    Abstract
    Lead-acid batteries have been used for over 150 years as a reliable means of storing electrical energy. These batteries have a variety of applications due to their high safety, reliable performance, and relatively easy manufacturing process, including in car starters, car lighting and combustion, electric vehicles (especially electric bicycles), and the resulting electrical energy storage. From renewable sources or pulsed power supplies in hybrid electric vehicles. Despite increasing advances in the performance and design of these batteries, there are still problems in this area. One of the most important of these is the electrolysis of water as a side reaction, which leads to the production... 

    Investigaion Properties of Electrocatalytic Transition Metal Chalcogenids Nanocomposite in Hydrogen and Oxygen Evolution Reactions

    , M.Sc. Thesis Sharif University of Technology Moazzeni, Mohammad (Author) ; Taherinia, Davood (Supervisor)
    Abstract
    Electrochemical water splitting which consists of two half-reactions, namely; the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), is an important process in electrochemical energy storage and sustainable production of energy. Therefore, the development of cost-effective and efficient electrocatalysts for water splitting has attracted a lot of interest. In this work, a new nanocomposite was prepared from cobalt diselenide and cerium (IV) oxide derived from calcination of a cerium-based metal-organic framework (Ce-MOF), via hydrothermal and electrodeposition methods. The structure and morphology of synthesized materials were investigated by XRD, FE-SEM, EDX, and BET... 

    Synthesis, Characterization, and Investigation of the Electrocatalytic Activity of Non-Precious Metal-Based Compounds Toward the Electrochemical Reduction of Carbon Dioxide

    , M.Sc. Thesis Sharif University of Technology Farahmand, Danial (Author) ; Taherinia, Davood (Supervisor)
    Abstract
    Emissions of carbon dioxide (CO2) from fossil fuels are a potential issue for the global climate. One way to address this challenge is to electrochemically convert CO2 molecules into carbon-reduced species such as alcohols, hydrocarbons, formates and other valuable products, which is a difficult process due to the slow kinetics of CO2 reduction. Therefore, the use of proper electrocatalyst while preventing undesirable adverse reactions can play an important role in the electrochemical reduction of CO2. In this study, synthesis of bimetallic Bi2O3@CuS composite as an advanced electrocatalyst for CO2 reduction in neutral pH environments has been investigated and reported. Bismuth oxide has...