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Does gold cluster promote or scavenge radicals? A controversy at DFT
, Article Journal of Physical Organic Chemistry ; Volume 31, Issue 3 , 2018 ; 08943230 (ISSN) ; Kassaee, M. Z ; Fattahi, A ; Sharif University of Technology
John Wiley and Sons Ltd
2018
Abstract
Anticancer character of gold cluster has been indicated through its free radical scavenging properties. This is in contrast to its free radical promoting ability suggested by other workers. Here, we address this controversy by probing the stabilizing effects of Au3 cluster on RO• vs its impacts on RO–H bond dissociation enthalpy, at B3LYP/ LACVP+* level (R═H, methyl, ethyl, n-propyl, i-propyl, n-butyl, t-butyl, and phenyl). In the presence of Au3 cluster, bond dissociation enthalpy of O–H bond and the spin density at the RO• oxygen are reduced dramatically. These are clear evidences for both the Au3 facilitation of the RO–H bond breakage and its scavenging of RO• radical. Since O–Au...
Delivery of hydrophobic anticancer drugs by hydrophobically modified alginate based magnetic nanocarrier
, Article Industrial and Engineering Chemistry Research ; Volume 57, Issue 3 , 2018 , Pages 822-832 ; 08885885 (ISSN) ; Amin, S. S ; Hosseini, H ; Sharif University of Technology
American Chemical Society
2018
Abstract
Since most of the anticancer drugs have low solubility in water, the clinical use of them is limited unless by some modification the solubility increases or the drug is carried with a soluble compartment. To solve this problem, we prepared a magnetic nanocarrier with a hydrophobic surface based on oleic acid chains in which hydrophobic drug molecules such as doxorubicin hydrochloride (DOX) and paclitaxel (PTX) are easily adsorbed onto the surface. Since the drug molecules are physically adsorbed on the surface, large amounts of DOX (282 mg·g-1) and PTX (316 mg·g-1) were immobilized onto the nanocarrier. Then, the surface of the drug loaded magnetic core was covered by a smart pH-sensitive...
Type-based sign modulation and its application for isi mitigation in molecular communication
, Article IEEE Transactions on Communications ; Volume 66, Issue 1 , 2018 , Pages 180-193 ; 00906778 (ISSN) ; Gohari, A ; Mirmohseni, M ; Nasiri Kenari, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
Abstract
While ISI is a common issue in classical communications, it is more challenging and prominent in the context of molecular communication, because one cannot readily combat ISI with classical channel equalization techniques. This is due to the fact that transmitter can only release a positive amount of concentration of a specific molecule into the medium. Previous works have proposed use of chemical reactions to remove molecules from the environment, and to effectively simulate negative signals. However, the differential equation describing a diffusion-reaction process is non-linear. This precludes the possibility of using Fourier transform tools. In this paper, a solution for simulating...
Recent advancements in aptamer-bioconjugates: Sharpening stones for breast and prostate cancers targeting
, Article Journal of Drug Delivery Science and Technology ; Volume 53 , 2019 ; 17732247 (ISSN) ; Shahraki, B. T ; Rabiee, N ; Afshari, R ; Fatahi, Y ; Dinarvand, R ; Ahmadi, S ; Bagherzadeh, M ; Rabiee, M ; Tahriri, M ; Tayebi, L ; Sharif University of Technology
Editions de Sante
2019
Abstract
Breast and prostate cancers are common types of cancers with various strategies, such as chemotherapy and radiotherapy, for their therapy. Since these methods have undesired side effects and poor target affinity, neoteric strategies—known as aptamer-based smart drug delivery systems (SDDSs)—have been developed in recent years to overcome the obstacles of current treatment, and investigated for a clinical trial. The high affinity and versatility of aptamers for binding to the corresponding targets make them highly noticeable agents in the drug delivery domains. In addition to their exceptional benefits, aptamers are able to overcome tumor resistance because of their high selectivity and low...
On Medium chemical reaction in diffusion-based molecular communication: A two-way relaying example
, Article IEEE Transactions on Communications ; Volume 67, Issue 2 , 2019 , Pages 1117-1132 ; 00906778 (ISSN) ; Aminian, G ; Mirmohseni, M ; Gohari, A ; Nasiri Kenari, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
Chemical reactions are a prominent feature of molecular communication systems, with no direct parallels in wireless communications. While chemical reactions may be used inside the transmitter nodes, receiver nodes, or the communication medium, we focus on its utility in the medium in this paper. Such chemical reactions can be used to perform computation over the medium as molecules diffuse and react with each other (physical-layer computation). We propose the use of chemical reactions for the following purposes: 1) to reduce signal-dependent observation noise of receivers by reducing the signal density; 2) to realize molecular physical-layer network coding (PNC) by performing the natural XOR...
Synthesis, first-principle simulation, and application of three-dimensional ceria nanoparticles/graphene nanocomposite for non-enzymatic hydrogen peroxide detection
, Article Journal of the Electrochemical Society ; Volume 166, Issue 5 , 2019 , Pages H3167-H3174 ; 00134651 (ISSN) ; Hatamie, A ; Berahman, M ; Simchi, M ; Angizi, S ; Rahmati, R ; Kennedy, J ; Simchi, A ; Sharif University of Technology
Electrochemical Society Inc
2019
Abstract
Owing to the exceptional properties of graphene and the crucial role of substrate on the performance of electrochemical biosensors, several graphene-based hybrid structures have recently emerged, yielding improved selectivity and sensitivity. To date, most of the reported biosensors utilize solution-driven graphene flakes with drawbacks of low conductivity (due to high inter-junction contact resistant) and structural fragility. Herein, we present a conductive three-dimensional CeO2 semiconductor nanoparticles/graphene nanocomposite, as a platform for sensitive detection of hydrogen peroxide, an important molecule in fundamental biological processes. The 3D conductive graphene architecture is...
Synthesis, first-principle simulation, and application of three-dimensional ceria nanoparticles/graphene nanocomposite for non-enzymatic hydrogen peroxide detection
, Article Journal of the Electrochemical Society ; Volume 166, Issue 5 , 2019 , Pages H3167-H3174 ; 00134651 (ISSN) ; Hatamie, A ; Berahman, M ; Simchi, M ; Angizi, S ; Rahmati, R ; Kennedy, J ; Simchi, A ; Sharif University of Technology
Electrochemical Society Inc
2019
Abstract
Owing to the exceptional properties of graphene and the crucial role of substrate on the performance of electrochemical biosensors, several graphene-based hybrid structures have recently emerged, yielding improved selectivity and sensitivity. To date, most of the reported biosensors utilize solution-driven graphene flakes with drawbacks of low conductivity (due to high inter-junction contact resistant) and structural fragility. Herein, we present a conductive three-dimensional CeO2 semiconductor nanoparticles/graphene nanocomposite, as a platform for sensitive detection of hydrogen peroxide, an important molecule in fundamental biological processes. The 3D conductive graphene architecture is...
Estimation of PC-SAFT binary interaction coefficient by artificial neural network for multicomponent phase equilibrium calculations
, Article Fluid Phase Equilibria ; Volume 510 , 2020 ; Abbasi, Z ; Bozorgmehry Boozarjomehry, R ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Perturbed-Chain Statistical Associating Fluid Theory Equation of State (PC-SAFT EoS) requires cross interaction parameter for each binary pair in the mixture. For real mixtures, these parameters should be corrected by binary interaction coefficients (kij's). The values of kij's are tuned by an optimization method in order to minimize the deviation from equilibrium data. The Particle Swarm Optimization (PSO) algorithm is employed for optimization of kij's due to the continuous nature of kij and highly nonlinear nature of PC-SAFT EoS. Although kij can be adjusted using the mentioned algorithm, it is cumbersome and highly time-consuming because the optimization should be performed for each pair...
Smart drug delivery: Capping strategies for mesoporous silica nanoparticles
, Article Microporous and Mesoporous Materials ; Volume 299 , 2020 ; Zare, H ; Razavi, S ; Mohammadi, H ; Torab Ahmadi, P ; Yazdani, N ; Bayandori, M ; Rabiee, N ; Izadi Mobarakeh, J ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Systematic delivery of therapeutic agents to specific sites, with a stimulus-responsive drug release profile is currently a rapidly growing area. Mesoporous silica nanoparticles (MSNs) are the useful platforms as drug/gene delivery systems due to their unique properties including the ability to control the pore size, high porosity, and morphology, which can directly affect the mechanism and profile of drug release. The appropriate fabrication strategy can tailor the particle shape and size, leading to enhanced delivery and release mechanisms. The MSN surface can be modified by using either organic or inorganic molecules to induce smart and site-specific drug delivery and release....
Green biodiesel production from various plant oils using nanobiocatalysts under different conditions
, Article Bioenergy Research ; Volume 13, Issue 2 , 2020 , Pages 552-562 ; Kazemeini, M ; Arpanaei, A ; Sharif University of Technology
Springer
2020
Abstract
The lipase-immobilized polyethyleneimine (PEI)- and polyacrylic acid (PAA)–coated magnetic silica nanocomposite particles (L-PEI-MS and L-PAA-MS, respectively) were prepared and applied at various transesterification reaction conditions. The reactions were carried out with soybean, sunflower, canola, and palm oils along with methanol or ethanol in the solvent-free and n-hexane systems. The highest fatty acid methyl ester (FAME) and fatty acid ethyl ester (FAEE) synthesis yields were obtained from the transesterification of palm oil, i.e., almost 7.7–10.2% higher than other oils. At the constant reaction conditions, the application of ethanol leads to higher (6.0–8.7%) reaction yields in...
Acidity enhancement of α-carbon of beta diketones via hydroxyl substituents: A density functional theory study
, Article Journal of Physical Organic Chemistry ; 2020 ; Fattahi, A ; Sharif University of Technology
John Wiley and Sons Ltd
2020
Abstract
Density functional theory method and B3LYP/6-311++G(d,p) level of theory were used to determine the acidity of α-carbon in the hydroxyl derivatives of beta diketones in the gas phase. An investigation of acidity strength in the gas phase indicates that α-carbon of hydroxyl derivatives of beta diketones become stronger acids than the α-carbon of beta diketone itself as their conjugate bases gain more stability via both enolate and hydrogen bond formation. Natural bond orbital and quantum theory of atoms in molecules analyses also confirm the role of hydrogen bond interactions on increasing the acidity of α-carbon of hydroxyl derivatives of beta diketones. © 2020 John Wiley & Sons, Ltd
Comparison of single and binary oxide sol-gel gas sensors based on titania
, Article Solid State Sciences ; Volume 10, Issue 7 , 2008 , Pages 884-893 ; 12932558 (ISSN) ; Fray, D. J ; Ghorbani, M ; Sharif University of Technology
Elsevier Masson SAS
2008
Abstract
A systematic comparison of single and binary metal oxides TiO2, TiO2-Ga2O3 and TiO2-Er2O3 thin film gas sensors with nanocrystalline and mesoporous microstructure, prepared by a new particulate sol-gel route, was conducted. The gas sensitivity was increased by introduction of Ga2O3 and Er2O3 into TiO2 film via two mechanisms, firstly through the inhibition of anatase-to-rutile transformation, since the anatase phase accommodates larger amounts of adsorbed oxygen, and secondly through the retardation of grain growth, since the higher surface area provides more active sites for gas molecule adsorption. The binary metal oxide gas sensors exhibited a remarkable response towards low...
Influence of secondary oxide phases on microstructural and gas sensitive properties of nanostructured titanium dioxide thin films
, Article Multi-functional Materials and Structures - International Conference on Multifunctional Materials and Structures, Hong Kong, P.R., 28 July 2008 through 31 July 2008 ; Volume 47-50 PART 1 , 2008 , Pages 41-44 ; 10226680 (ISSN); 0878493786 (ISBN); 9780878493784 (ISBN) ; Ghorbani, M ; Fray, D. J ; Sharif University of Technology
Trans Tech Publications
2008
Abstract
A systematic comparison of single and binary metal oxide T1O2, TiO2-Ga2O3, TiO2-Er 2O3 and TiO2-Ta2O5 gas sensors with nanocrystalline and mesoporous microstructure, prepared by sol-gel route, was conducted. The gas sensitivity was increased by secondary phase introduction into TiO2 film via two mechanisms, firstly through the inhibition of anatase-to-rutile transformation, since the anatase phase accommodates larger amounts of adsorbed oxygen, and secondly through the retardation of grain growth, since the higher surface area provides more active sites for gas molecule adsorption. The binary metal oxides exhibited a remarkable response towards low concentrations of CO and NO2 gases at low...
Mechanistic investigation of the synergy of a wide range of salinities and ionic liquids for enhanced oil recovery: Fluid-fluid interactions
, Article Energy and Fuels ; Volume 35, Issue 4 , 2021 , Pages 3011-3031 ; 08870624 (ISSN) ; Maghsoudian, A ; Shirazi, M ; Tamsilian, Y ; Kord, S ; Sheng, J.J ; Sharif University of Technology
American Chemical Society
2021
Abstract
In this paper, the performance of three imidazolium-based ionic liquids (ILs) including 1-hexyl-3-methylimidazolium chloride ([HMIM][Cl] or IL6), 1-octyl-3-methylimidazolium chloride ([OMIM][Cl] or IL8), and 1- dodecyl-3-methylimidazolium chloride ([DMIM][Cl] or IL12) in reducing the interfacial tension (IFT) between crude oil and IL solutions was analyzed for the first time under a wide range of salinities (1000 to 195 476 ppm) at a reservoir temperature of 80 °C. The purpose was to microscopically analyze the occurring phenomenon at the fluid-fluid interface to determine the mechanism leading to oil extraction and to address the existing ambiguities in the literature concerning the...
The effect of brine salinity and oil components on dynamic IFT behavior of oil-brine during low salinity water flooding: Diffusion coefficient, EDL establishment time, and IFT reduction rate
, Article Journal of Petroleum Science and Engineering ; Volume 196 , 2021 ; 09204105 (ISSN) ; Ayatollahi, S ; Fatemi, M ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Dynamic behavior of fluid-fluid interactions can potentially affect the performance of any enhanced oil recovery (EOR) process including low salinity water flooding. In this work, dynamic interfacial tension (IFT) of crude-oil/brine system is measured in a wide range of salinity of sea water (SW), from 50-time diluted sea water (SW50D) to 2-time concentrated sea water (SW2C). Contrary to the most of published IFT trends in the literature, for the system under investigation here, as the brine salinity increases the crude-oil/brine IFT reduces, which cannot be explained using the existing theories. The lack of a physical model to explain the observed phenomena was the motivation to develop a...
Recent trends in application of chemometric methods for GC-MS and GC×GC-MS-based metabolomic studies
, Article TrAC - Trends in Analytical Chemistry ; Volume 138 , 2021 ; 01659936 (ISSN) ; Hashemi Nasab, F. S ; Golpelichi, F ; Sabouruh, N ; Parastar, H ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Metabolomics is the science of studying small molecules (metabolites) in biological systems with the aim of getting insight into cells, biofluids and organisms. Chemometric methods are powerful tools to address data problems generated in metabolomic studies and to extract valuable information. This review focuses mainly on a range of chemometric methods used for processing of metabolomics data generated from gas chromatography-mass spectrometry (GC-MS) and comprehensive two-dimensional gas chromatography-mass spectrometry (GC × GC-MS). Herein, essential skills used for preprocessing of raw data, multivariate resolution, pattern recognition, variable selection and identification of...
Low loaded MoS2/Carbon cloth as a highly efficient electrocatalyst for hydrogen evolution reaction
, Article International Journal of Hydrogen Energy ; 2021 ; 03603199 (ISSN) ; Mehdipour, H ; Moshfegh, A. Z ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Active edge sites of MoS2 nanosheets exhibit promising futures for hydrogen evolution reaction (HER), comparable with remarkable performances of highly cost platinum. However, 3D structures of MoS2 suffer from a lack of high mobility and unexposed active sites which lower the electrocatalytic activity. In this study, we show that there is a balance between increasing the active sites on the one hand and managing the charge transfer to facilitate the reaction on the other hand, and achieving this balance increases the efficiency of the electrocatalyst tremendously. For this purpose, we directly attached exfoliated MoS2 nanosheets onto carbon cloth (CC) substrate as a 3D network of conductive...
Gold at crossroads of radical generation and scavenging at density functional theory level: Nitrogen and oxygen free radicals versus their precursors in the face of nanogold
, Article Journal of Physical Organic Chemistry ; Volume 34, Issue 1 , 2021 ; 08943230 (ISSN) ; Kassaee, M. Z ; Ayoubi Chianeh, M ; Fattahi, A ; Sharif University of Technology
John Wiley and Sons Ltd
2021
Abstract
In our previous report (J. Phys. Org. Chem., 2017), we discussed the dual behavior of gold nanocluster (Au3 NC), where it scavenged reactive oxygen species (ROS) while promoted their generation to a lesser extent. Continuing this quest, we investigate the effects of Au3 NC on common reactive nitrogen species (RNS: O=N˙ and O=N-O) and their precursors (O=N-H and O=N-O-H, respectively), at B3LYP/LACVP+* level of theory. We compare the results with those of prevalent ROS (H-O˙ and H-O-O˙) and their precursors (H-O-H and H-O-O-H, respectively). To this end, various parameters are probed such as binding energy (Eb), bond dissociation energy (BDE), bond lengths, Mullikan spin density (MSD),...
Gold at crossroads of radical generation and scavenging at density functional theory level: Nitrogen and oxygen free radicals versus their precursors in the face of nanogold
, Article Journal of Physical Organic Chemistry ; Volume 34, Issue 1 , 2021 ; 08943230 (ISSN) ; Kassaee, M.Z ; Ayoubi-Chianeh, M ; Fattahi, A ; Sharif University of Technology
John Wiley and Sons Ltd
2021
Abstract
In our previous report (J. Phys. Org. Chem., 2017), we discussed the dual behavior of gold nanocluster (Au3 NC), where it scavenged reactive oxygen species (ROS) while promoted their generation to a lesser extent. Continuing this quest, we investigate the effects of Au3 NC on common reactive nitrogen species (RNS: O=N˙ and O=N-O) and their precursors (O=N-H and O=N-O-H, respectively), at B3LYP/LACVP+* level of theory. We compare the results with those of prevalent ROS (H-O˙ and H-O-O˙) and their precursors (H-O-H and H-O-O-H, respectively). To this end, various parameters are probed such as binding energy (Eb), bond dissociation energy (BDE), bond lengths, Mullikan spin density (MSD),...
Comparison among various configurations of hybrid distillation–membrane setups for the energy efficiency improvement of bioethanol distillery: a simulation study
, Article Journal of Chemical Technology and Biotechnology ; October , 2021 ; 02682575 (ISSN) ; Aslam, Z ; Ali, U ; Akhtar, A ; Sharif University of Technology
John Wiley and Sons Ltd
2021
Abstract
BACKGROUND: Hybrid distillation–membrane setups have attracted attention in recent years due to their lower energy usage for ethanol purification. Membrane separation processes operate without heating that reduces energy demand. However, it is somewhat challenging to select the optimal material and process for a membrane purifying ethanol, especially to get an ethanol purity of 99.99% with maximum recovery. RESULTS: In this study, three different configurations of hybrid distillation–membrane setups are proposed consisting of distillation–pervaporation/vapor permeation processes by considering ceramic, polymeric and composite membranes. The design of hybrid processes is performed by coupling...