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51.
Kurosh Rad‐Moghadam Abbas Ali Esmaeili Saeid Amini Ghalandarabad Fereshteh Hoseininejad Seyyed Adel Fallah‐Rasoulinejad Samaneh Kiani 《Journal of heterocyclic chemistry》2014,51(6):1791-1796
The titled products comprising of two mutually merged bioactive nucleuses, 2‐aminobenzo[d]thiazole and 2,5‐dihydropyrrole rings, were obtained from the reaction between dialkyl acetylenedicarboxylates and alkyl 2‐(benzo[d]thiazol‐2‐yl)amino‐2‐oxoacetates in the presence of triphenylphosphine at RT. 相似文献
52.
Mahdiyeh Naderzadeh Mohammad Reza Monazzam Parvin Nassiri Samaneh Momen Bellah Fard 《Applied Acoustics》2011,72(6):393-398
The scope of this paper is to study the performance of noise barriers treated with different diffusers with/without a perforated sheet. We investigated the barrier insertion loss using a 2D boundary element method (BEM). To obtain a better depth sequence, a Random Sequence Diffuser (RSD) was designed. The results clearly showed that employing a "RSD" instead of the most popular Schroeder diffusers (Quadratic Residue Diffuser and Primitive Root Diffuser) increased the acoustic performance. We also found that the diffuser performance improved by treating the diffuser with perforated sheets either on the top surface or inside the wells. The addition of these perforated sheets inside the "RSD" (barrier model "RPI2") improved the performance by 3.59 dB (A). 相似文献
53.
Mahdiar Khakinejad Samaneh Ghassabi Kondalaji Hossein Maleki James R. Arndt Gregory C. Donohoe Stephen J. Valentine 《Journal of the American Society for Mass Spectrometry》2014,25(12):2103-2115
The gas-phase conformations of electrosprayed ions of the model peptide KKDDDDIIKIIK have been examined by ion mobility spectrometry (IMS) and hydrogen deuterium exchange (HDX)-tandem mass spectrometry (MS/MS) techniques. [M+4H]4+ ions exhibit two conformers with collision cross sections of 418 Å2 and 471 Å2. [M+3H]3+ ions exhibit a predominant conformer with a collision cross section of 340 Å2 as well as an unresolved conformer (shoulder) with a collision cross section of ~367 Å2. Maximum HDX levels for the more compact [M+4H]4+ ions and the compact and partially-folded [M+3H]3+ ions are ~12.9, ~15.5, and ~14.9, respectively. Ion structures obtained from molecular dynamics simulations (MDS) suggest that this ordering of HDX level results from increased charge-site/exchange-site density for the more compact ions of lower charge. Additionally, a new model that includes two distance calculations (charge site to carbonyl group and carbonyl group to exchange site) for the computer-generated structures is shown to better correlate to the experimentally determined per-residue deuterium uptake. Future comparisons of IMS-HDX-MS data with structures obtained from MDS are discussed with respect to novel experiments that will reveal the HDX rates of individual residues. Graphical Abstract
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54.
Samaneh Mozaffari Mohamad Reza Nateghi Mahmood Borhanizarandi 《Journal of Solid State Electrochemistry》2014,18(9):2589-2598
A new water-based solution of ion-conductive polymeric gel electrolyte composed of polyethylene glycol and polyvinylpyrrolidone as gel-forming substances, I?/I3 ? as reversible redox couple, and various ratios of acetonitrile/water solvents was prepared and used in the fabrication of dye-sensitized solar cells. The effects of water on the electrochemical behavior of the prepared electrolyte solutions were examined by the cyclic voltammetry and electrochemical impedance spectroscopy techniques. Electrochemical impedance spectroscopy was employed to quantify the charge-transfer resistance and the electron lifetime at the TiO2 conduction band. The characteristic peak shifted to a lower frequency in the Bode phase plot, which is an indication of a longer electron lifetime for the cell containing more water content. Photovoltaic performance of the cells prepared by the new water-based gel electrolyte was studied. Changes in the current density–voltage (J–V) characteristics can be explained based on the effect of water on the energetics and kinetics of charge transport and charge recombination in the dye-sensitized solar cells (DSSCs). It was observed that the increase in open-circuit voltage (V oc) and fill factor and decrease in J SC were noticeable for cells containing water-based gel electrolyte. It was indicated that the charge recombination between injected electrons and electron acceptors (polyiodide) in the redox electrolyte was remarkably inhibited by the increase of water. The photovoltaic performance stability of the DSSC containing gel electrolyte solution including 50 wt% of water was examined, and it was shown that it is more stable than conventional cells considerably for 168 h. Energy conversion efficiency of 2.30 % was achieved, under illumination with a simulated solar light of 100 mW cm?2. 相似文献
55.
Samaneh Raouf Yazdinezhad Ana Ballesteros-Gómez Loreto Lunar Soledad Rubio 《Analytica chimica acta》2013
Hemimicelles of tetradecanoate chemisorbed onto magnetic nanoparticles (MNPs) are here proposed as a sorbent for the single-step extraction and cleanup of bisphenol A (BPA) in soft drinks. The purpose of this work was to develop a simple, rapid and low-cost sample treatment suitable to assess the human exposure to BPA from this type of high consumption food. The nanoparticles were easily coated by mixing commercially available magnetite of 20–30 nm mean particle diameter with tetradecanoate at 85 °C for 30 min. The extraction/cleanup procedure involved stirring the samples (3 mL) with 200 mg of tetradecanoate-coated MNPs for 20 min, isolating the sorbent with a Nd–Fe–B magnet and eluting BPA with methanol. The extraction efficiency was not influenced by salt concentrations up to 1 M and pH values over the range 4–9. No cleanup of the extracts was needed, and the method proved matrix-independent. The extracts were analyzed by liquid chromatography, electrospray ionization tandem mass spectrometry. Quantitation was performed by internal standard calibration using BPA-13C12. The limit of quantitation obtained for the method, 0.03 ng mL−1, was below the usual range of concentrations reported for BPA in soft drinks (0.1–3.4 ng mL−1). The proposed method was successfully applied to the determination of BPA in different samples acquired from various supermarkets in southern Spain; the concentrations found ranged from 0.066 to 1.08 ng mL−1. Recoveries from samples spiked with 0.33 ng mL−1 of BPA ranged from 91% to 105% with relative standard deviations from 3% to 8%. 相似文献
56.
Behrooz Maleki Saba Hemmati Reza Tayebee Sirous Salemi Yasaman Farokhzad Mehdi Baghayeri Farrokhzad Mohammadi Zonoz Elahe Akbarzadeh Rohollah Moradi Azam Entezari Mohammad Reza Abdi Samaneh Sedigh Ashrafi Fereshteh Taimazi Majid Hashemi 《Helvetica chimica acta》2013,96(11):2147-2151
A convenient synthesis of sulfonamides and sulfonyl azides from thiols is described. In situ preparation of sulfonyl chlorides from thiols was accomplished by oxidation with chloramine‐T (=N‐chlorotosylamide=N‐chloro‐4‐methylbenzenesulfonamide), tetrabutylammonium chloride (Bu4NCl), and H2O. The sulfonyl chlorides were then further allowed to react with excess amine or NaN3 in the same pot. 相似文献
57.
Samaneh Soloukipour Ehsan Saljoughi Seyed Mahmoud Mousavi Mahdi Pourafshari Chenar 《先进技术聚合物》2017,28(1):113-123
In the present research, novel polyether block amide (PEBA)/polyvinyldene fluoride (PVDF) blend pervaporation (PV) membranes were prepared for the removal of isopropyl alcohol (IPA) from the aqueous solution. The membranes obtained at PEBA/PVDF ratios of 100/0, 95/5, and 90/10 were characterized using scanning electron microscopy, thermogravimetric analysis, water contact angle measurement, and tensile test. Moreover, the PV performance of the membranes was assessed via separation of IPA from the aqueous solution. The blended membranes exhibited higher hydrophobicity and separation factor as well as lower permeability in comparison with the pure PEBA membrane. The blended membrane that was prepared at PEBA/PVDF ratio of 95/5 was found as the optimum membrane providing PV separation index of 3171 that appeared to be the maximum value. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
58.
Fundamental Study of Pore Scale Mechanisms in Microbial Improved Oil Recovery Processes 总被引:1,自引:0,他引:1
A fundamental study of microscopic mechanisms and pore-level phenomena in the Microbial Improved Oil Recovery method has been
investigated. Understanding active mechanisms to increase oil recovery is the key to predict and plan MIOR projects successfully.
This article presents the results of visualization experiments carried out in a transparent pore network model. In order to
study the pore scale behavior of bacteria, dodecane and an alkane oxidizing bacterium, Rhodococcus sp. 094, suspended in brine, are examined for evaluating the performance of bacterial flooding in the glass micromodel. The
observations show the effects of bacteria on remaining oil saturation, allowing us to get better insight on the mechanisms.
Bacterial mass composed of bacteria and bioproducts growth in the fluid interfaces and pore walls have been recorded and are
presented. No gas is observed throughout any of the experiments. The biomass blocks some pores and pore-throats, and thereby
changing the flow pattern. As a consequent, the flow pattern change together with the previously proposed mechanisms, including
the interfacial tension reduction and wettability changes are recognized as active mechanisms in the MIOR process. 相似文献
59.
Khalilzadeh Mohammad A. Hossaini Zinatossadat Kharian Samaneh 《Molecular diversity》2010,14(3):605-609
Molecular Diversity - An efficient synthesis of 2H-pyridinyl-2-butenedioate derivatives via reaction of dimethyl methoxymalonate and dialkyl acetylenedicarboxylate in the presence of N-nucleophiles... 相似文献
60.
Samaneh Abbasi Pierre J. Carreau Abdessalem Derdouri Michel Moan 《Rheologica Acta》2009,48(9):943-959
This paper is concerned with several issues related to the rheological behavior of polycarbonate/multiwalled carbon nanotube
nanocomposites. The composites were prepared by diluting a masterbatch of 15 wt.% nanotubes using melt-mixing method, and
the dispersion was analyzed by SEM, TEM, and AFM techniques. To understand the percolated structure, the nanocomposites were
characterized via a set of rheological, electrical, and thermal conductivity measurements. The rheological measurements revealed
that the structure and properties were temperature dependent; the percolation threshold was significantly lower at higher
temperature suggesting stronger nanotube interactions. The nanotube networks were also sensitive to the steady shear deformation
particularly at high temperature. Following preshearing, the elastic modulus decreased markedly suggesting that the nanotubes
became more rigid. These results were analyzed using simple models for suspensions of rod-like particles. Finally, the rheological,
electrical, and thermal conductivity percolation thresholds were compared. As expected, the rheological threshold was smaller
than the thermal and electrical threshold. 相似文献