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ZrOCl2·8H2O on montmorillonite K10 accelerated conjugate addition of amines to α,β-unsaturated alkenes under solvent-free conditions
, Article Tetrahedron ; Volume 62, Issue 4 , 2006 , Pages 672-677 ; 00404020 (ISSN) ; Eftekhari-Sis, B ; Abdollahifar, A ; Khalili, B ; Sharif University of Technology
2006
Abstract
At room temperature, ZrOCl2·8H2O on montmorillonite K10 efficiently catalyzes conjugate addition of amines to a variety of conjugated alkenes such as α,β-unsaturated carbonyl compounds, carboxylic esters, nitriles and amides under solvent-free conditions. The catalyst can be recycled for subsequent reactions without any appreciable loss of efficiency. © 2005 Elsevier Ltd. All rights reserved
Solvent parameters effects on the second-order rate constants of the reaction of 2-chloro-3,5-dinitropyridine with aniline in aqueous solutions of alcohols
, Article Progress in Reaction Kinetics and Mechanism ; Volume 31, Issue 2 , 2006 , Pages 117-127 ; 14686783 (ISSN) ; Masumpour, M. S ; Gholami, M. R ; Sharif University of Technology
Science Reviews Ltd
2006
Abstract
Aromatic nucleophilic substitution reaction kinetics of 2-chloro-3,5-dinitropyridine with aniline was studied in aqueous solutions of methanol, ethanol, and 2-propanol at room temperature. The obtained results for aqueous solutions indicate that the second-order rate constants are in order of 2-propanol>ethanol>methanol with a maximum at water mole fraction of 0.9. The influence of solvent parameters including normalized polarity (E TN), dipolarity/polarisability (π*), and hydrogen bond donor acidity (α) on the second-order rate constants were investigated and multiple regressions gave much better results with regard to single parameter regressions. Dipolarity/polarisability and hydrogen...
Automated trace determination of earthy-musty odorous compounds in water samples by on-line purge-and-trap-gas chromatography-mass spectrometry
, Article Journal of Chromatography A ; Volume 1136, Issue 2 , 2006 , Pages 170-175 ; 00219673 (ISSN) ; Lacorte, S ; Bagheri, H ; Barceló, D ; Sharif University of Technology
2006
Abstract
An automated technique based on purge-and-trap coupled to gas chromatography with mass spectrometric detection has been developed and optimized for the trace determination of five of the most important water odorants; 2-isopropyl-3-methoxypyrazine, 2-isobutyl-3-methoxypyrazine, 2-methylisoborneol, 2,4,6-trichloroanisole and geosmin. The extraction method was absolutely solvent-free. Analytes were purged from 20 ml of water sample containing sodium chloride at room temperature by a flow of He and trapped on a Tenax sorbent. The desorption step was performed with helium and temperature programming and desorbed analytes were directly transferred to a gas chromatograph coupled to a mass...
N-benzyl-DABCO-tribromide as an efficient and mild reagent for deprotection of dithioacetals
, Article Synthetic Communications ; Volume 36, Issue 8 , 2006 , Pages 1093-1096 ; 00397911 (ISSN) ; Boeini, H. Z ; Zargarani, D ; Bardajee, G. R ; Sharif University of Technology
2006
Abstract
N-Benzyl-DABCO-ammonium tribromide was found to be an efficient and recyclable reagent for the deprotection of dithioacetals in dichloromethane/ methanol at room temperature. The reaction can be performed cleanly, in short time, and in high yield. Copyright © Taylor & Francis Group, LLC
Improved green biosynthesis of chitosan decorated Ag- and Co3O4-nanoparticles: A relationship between surface morphology, photocatalytic and biomedical applications
, Article Nanomedicine: Nanotechnology, Biology, and Medicine ; Volume 32 , 2021 ; 15499634 (ISSN) ; Rabiee, N ; Bagherzadeh, M ; Ghadiri, A.M ; Fatahi, Y ; Dinarvand, R ; Webster, T. J ; Sharif University of Technology
Elsevier Inc
2021
Abstract
AgNPs@Chitosan and Co3O4-NPs@Chitosan were fabricated with Salvia hispanica. Results showed MZI values of 5 and 30 mm for Co3O4-NPs- and AgNPs@Chitosan against S. aureus, and 15 and 21 mm for Co3O4-NPs- and AgNPs@Chitosan against E. coli (24 h, 20 μg/mL), respectively. MTT assays showed up to 80% and 90%, 71% and 75%, and 91% and 94% mammalian cell viability for the green synthesized, chemically synthesized AgNPs and green synthesized AgNPs@Chitosan for HEK-293 and PC12 cells, respectively, and 70% and 71%, 59% and 62%, and 88% and 73% for the related Co3O4-NPs (24 h, 20 μg/mL). The photocatalytic activities showed dye degradation after 135 and 105 min for AgNPs@Chitosan and...
Water repellent room temperature vulcanized silicone for enhancing the long-term stability of perovskite solar cells
, Article Solar Energy ; Volume 218 , 2021 , Pages 28-34 ; 0038092X (ISSN) ; Heydari, M ; Mohammadi, M ; Parand, P ; Taghavinia, N ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
A key direction toward enhancing the long term and outdoor stability of the perovskite solar cells is encapsulation. As a result, a suitable encapsulation package is required to prevent moisture and oxygen penetration toward the perovskite solar cells. In this work, a low-cost commercially available bilayer structure of poly (methyl methacrylate)/ room-temperature vulcanizing silicone rubber (RTV) encapsulation package for enhancing the long term stability of the perovskite solar cells has been investigated. Encapsulated cells retained more than 80% of the initial efficiency at the environmental condition of 50% moisture, and room temperature after 1000 h, however reference cell efficiency...
Oxidation effects on transport characteristics of nanoscale MOS capacitors with an embedded layer of silicon nanocrystals obtained by low energy ion implantation
, Article Materials Science and Engineering B: Solid-State Materials for Advanced Technology ; Volume 124-125, Issue SUPPL , 2005 , Pages 494-498 ; 09215107 (ISSN) ; Shalchian, M ; Benassayag, G ; Coffin, H ; Bonafos, C ; Schamm, S ; Atarodi, S. M ; Claverie, A ; Sharif University of Technology
2005
Abstract
In this paper, we have studied the effect of annealing under slightly oxidizing ambient (N2 + O2) on the structural and electrical characteristics of a limited number of silicon nanoparticles embedded in an ultra-thin SiO2 layer. These nanoparticles were synthesized by ultra-low energy (1 keV) ion implantation and annealing. Material characterization techniques including transmission electron microscopy (TEM), Fresnel imaging and spatially resolved electron energy loss spectroscopy (EELS) have been used to evaluate the effects of oxidation on structural characteristics of nanocrystal layer. Electrical transport characteristics have been measured on less than one hundred nanoparticles by...
The effects of oxidation conditions on structural and electrical properties of silicon nanoparticles obtained by ultra-low-energy ion implantation
, Article Nanotechnology ; Volume 16, Issue 12 , 2005 , Pages 2987-2992 ; 09574484 (ISSN) ; Shalchian, M ; Ben Assayag, G ; Coffin, H ; Bonafos, C ; Schamm, S ; Atarodi, S. M ; Claverie, A ; Sharif University of Technology
2005
Abstract
In this paper, we have studied the effect of annealing under slightly oxidizing ambient (N2+O2) on the structural and electrical characteristics of a limited number of silicon nanoparticles embedded in an ultra-thin SiO2 layer. These nanoparticles were synthesized by ultra-low-energy (1 keV) ion implantation and annealing. Specific experimental methods have been used to characterize the ncs populations. They include transmission electron microscopy (TEM) Fresnel imaging for evaluating the distances and widths of interest and spatially resolved electron energy loss spectroscopy (EELS) using the spectrum-imaging mode of a scanning transmission electron microscope (STEM) to measure the size...
Solid lithium perchlorate as a powerful catalyst for the synthesis of β-aminoalcohols under solvent-free conditions
, Article Canadian Journal of Chemistry ; Volume 83, Issue 5 , 2005 , Pages 505-507 ; 00084042 (ISSN) ; Saidi, M. R ; Sharif University of Technology
2005
Abstract
Lithium perchlorate catalyzed the ring opening of epoxides with amines to provide the corresponding β-aminoalcohols in excellent yields with high regioselectivity. The reaction proceeds rapidly under mild and neutral conditions and worked well with primary, secondary, aliphatic, aromatic, and hindered amines in short times at room temperature, in the absence of solvent. © 2005 NRC Canada
Room-temperature quantum effect in silicon nanoparticles obtained by low-energy ion implantation and embedded in a nanometer scale capacitor
, Article Applied Physics Letters ; Volume 86, Issue 16 , 2005 , Pages 1-3 ; 00036951 (ISSN) ; Grisolia, J ; Assayag, G. B ; Coffin, H ; Atarodi, S. M ; Claverie, A ; Sharif University of Technology
2005
Abstract
In this article, we present the room-temperature current-voltage characteristics of a nanometer scale (100×100 nm2) metal-oxide-semiconductor capacitor containing few (less than 100) silicon nanoparticles. The layer of silicon nanoparticles is synthesized within the oxide of this capacitor by ultra low-energy ion implantation and annealing. Current fluctuations in the form of discrete current steps and sharp peaks appeared in the static and dynamic I (V) characteristics of the capacitor. These features have been associated to quantized charging and discharging of the nanoparticles and the resulting Coulomb interaction to the tunneling current. © 2005 American Institute of Physics
An intriguing effect of lithium perchlorate dispersed on silica gel in the bromination of aromatic compounds by N-bromosuccinimide
, Article Canadian Journal of Chemistry ; Volume 83, Issue 2 , 2005 , Pages 146-149 ; 00084042 (ISSN) ; Azizi, N ; Saidi, M. R ; Sharif University of Technology
2005
Abstract
A convenient and efficient procedure for electrophilic aromatic bromination has been developed by mixing of N-bromosuccinimide and an aromatic compound at room temperature on the surface of silica gel mixed with solid anhydrous LiClO4. All of the substrates examined underwent clean electrophilic aromatic bromination in reaction times of a few minutes to afford the corresponding bromoarenes under neutral conditions in excellent yield. In the case of thiophenol, no substitution reaction occurred, and the corresponding disulfide was obtained in excellent yield. © 2005 NRC Canada
Green synthesis of PEG-coated MIL-100(Fe) for controlled release of dacarbazine and its anticancer potential against human melanoma cells
, Article International Journal of Pharmaceutics ; Volume 618 , 2022 ; 03785173 (ISSN) ; Vossoughi, M ; Bagherzadeh, M ; Pooshang Bagheri, K ; Sharif University of Technology
Elsevier B.V
2022
Abstract
In this study, the potential of using MIL-100(Fe) metal–organic framework (MOF) for loading and controlling the release of dacarbazine (DTIC) was evaluated for in vitro treatment of melanoma. The drug loading was performed during the green synthesis of MIL-100(Fe) in an aqueous media without using any harmful solvents, to obtain MIL-DTIC. The surface of this structure was then coated with polyethylene glycol (PEG) in the same aqueous solution to synthesize MIL-DTIC-PEG. The synthesized samples were characterized using various methods. Their release profile was studied in phosphate-buffered saline (PBS) and simulated cutaneous medium (SCM). The cytotoxicity of DTIC and its nano-MOF...
Label-Free real-time detection of HBsAg using a QCM immunosensor
, Article Clinical Laboratory ; Volume 68, Issue 4 , 2022 , Pages 707-720 ; 14336510 (ISSN) ; Ghavidel, A ; Ahangari Cohan, R ; Hamidi Fard, M ; Khoobi, M ; Aghasadeghi, M ; Norouzian, D ; Sharif University of Technology
Verlag Klinisches Labor GmbH
2022
Abstract
Background: Hepatitis B virus surface antigen (HBsAg) is an important protein in both diagnosis and prevention of hepatitis B infection. In the current study, a piezoelectric immunosensor based on antibody-antigen interaction was designed to detect HBsAg. A quartz crystal microbalance system was employed to detect antibody-antigen interaction. Methods: At first, an oscillator was designed to measure the resonant frequency affected by the reactants using IC 74LVC1GX04. Antibody against HBsAg was immobilized on 10 MHz AT-cut quartz crystal. The surface modifications were monitored by atomic force microscopy (AFM) and contact angle measurements. Different concentrations of antibody were used...
Magnetic, thermally stable, and superhydrophobic polyurethane sponge: A high efficient adsorbent for separation of the marine oil spill pollution
, Article Chemosphere ; Volume 287 , 2022 ; 00456535 (ISSN) ; Pourjavadi, A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Herein, we demonstrated a facile method for the fabrication of magnetic and superhydrophobic polyurethane sponge with water contact angle of 159° as an adsorbent for cleanup the marine oil spill pollution. For this aim, a polyurethane sponge was coated with carbon black (CB), hexagonal boron nitride (h-BN)@Fe3O4, and acrylic resin and then characterized by different techniques. Owing to the chemical and thermal stability of h-BN and CB, the modified sponge was stable under corrosive conditions (pH = 1–14 and salt solutions) and at different temperatures (−12 °C–105 °C). In addition to common oils and organic solvents, we also used the real spilled oils containing monoaromatics and...
Tunable magneto-optical and interfacial defects of Nd and Cr-doped bismuth ferrite nanoparticles for microwave absorber applications
, Article Journal of Colloid and Interface Science ; Volume 608 , 2022 , Pages 1868-1881 ; 00219797 (ISSN) ; Lu, Y ; Hu, E ; Wang, B ; Niaz Akhtar, M ; Noor, A ; Akbar, M ; Yousaf Shah, M. A. K ; Wang, F ; Zhu, B ; Sharif University of Technology
Academic Press Inc
2022
Abstract
Tunable microwave absorption characteristics are highly desirable for industrial applications such as antenna, absorber, and biomedical diagnostics. Here, we report BiNdxCrxFe1-2xO3 (x = 0, 0.05, 0.10, 0.15) nanoparticles (NPs) with electromagnetic matching, which exhibit tunable magneto-optical and feasible microwave absorption characteristics for microwave absorber applications. The experimental results and theoretical calculations demonstrate the original bismuth ferrite (BFO) crystal structure, while Nd and Cr injection in the BFO structure may cause to minimize dielectric losses and enhance magnetization by producing interfacial defects in the spinel structure. Nd and Cr co-doping plays...
A facile one-pot, four-component synthesis of (Z)-isomer of rhodanine-oxindole derivatives under environmentally benevolent conditions
, Article Synthetic Communications ; Volume 52, Issue 2 , 2022 , Pages 175-184 ; 00397911 (ISSN) ; Aghamiri, B ; Jalalinik, M ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
Herein, an efficient and sustainable one-pot, four-component access to rhodanine-oxindole derivatives is achieved by a reaction between primary amines, carbon disulfide, ethyl chloroacetate, and cyano-substituted alkenyl oxindoles. The reaction was conducted without any harsh conditions as well as exhausting workup in polyethylene glycol (PEG) as a green solvent at room temperature and delivered rhodanine-oxindole products in high yield. This publication is the first easy protocol to be reported for the rapid construction of new rhodanine-oxindole derivatives at room temperature without harsh conditions and via multicomponent reaction. © 2021 Taylor & Francis Group, LLC