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61.
Esmaeil Ebrahimi Ahmad Sheykhi Hamzeh Alavirad 《Central European Journal of Physics》2013,11(7):949-960
We investigate the generalized Quantum Chromodynamics (QCD) ghost model of dark energy in the framework of Einstein gravity. First, we study the non-interacting generalized ghost dark energy in a flat Friedmann-Robertson-Walker (FRW) background. We obtain the equation of state parameter, w D = p/ρ, the deceleration parameter, and the evolution equation of the generalized ghost dark energy. We find that, in this case, w D cannot cross the phantom line (w D > ?1) and eventually the universe approaches a de-Sitter phase of expansion (w D → ?1). Then, we extend the study to the interacting ghost dark energy in both a flat and non-flat FRW universe. We find that the equation of state parameter of the interacting generalized ghost dark energy can cross the phantom line (w D < ?1) provided the parameters of the model are chosen suitably. Finally, we constrain the model parameters by using the Markov Chain Monte Carlo (MCMC) method and a combined dataset of SNIa, CMB, BAO and X-ray gas mass fraction. 相似文献
62.
Mehdi M. Baradarani Bahman Ebrahimi Saatluo Shiva Ghabeli Zahra Shokri Masoumeh Shahbazi John A. Joule 《Journal of heterocyclic chemistry》2019,56(7):1999-2007
The tricyclic isatin, 5,6‐dihydro‐4H‐pyrrolo[3,2,1‐ij]quinoline‐1,2‐dione, undergoes three‐component, one‐pot reactions with 1‐aryl‐3‐methylpyrazole‐5‐amines and cyclohexane‐1,3‐diones producing hexacyclic spiro products, hexahydrospiro[pyrazolo[3,4‐b]quinoline‐4,1‐pyrrolo[3,2,1‐ij]quinoline‐2′,5(1H,4′H)‐diones]. Comparable spiro condensation products are also obtained using 4‐hydroxy‐2H‐1‐benzopyran‐2‐one in place of cyclohexane‐1,3‐diones. 相似文献
63.
Samadi Morasae Zirak Mohammad Naseri Amene Kheirabadi Malihe Ebrahimi Mahdi Moshfegh Alireza Z. 《Research on Chemical Intermediates》2019,45(4):2197-2254
Research on Chemical Intermediates - Photocatalysis using semiconductors has emerged as a promising wastewater treatment process to overcome the major challenges faced by conventional technologies.... 相似文献
64.
M. Vogel G. Birkl M. S. Ebrahimi D. von Lindenfels A. Martin G. G. Paulus W. Quint S. Ringleb Th. Stöhlker M. Wiesel 《Hyperfine Interactions》2015,230(1-3):65-71
We present two Penning trap experiments concerned with different aspects of the physics of extreme electromagnetic fields, the ARTEMIS experiment designed for bound-electron magnetic moment measurements in the presence of the extremely strong fields close to the nucleus of highly charged ions, and the HILITE experiment, in which well-defined ion targets are to be subjected to high-intensity laser fields. 相似文献
65.
Ghorbani Bahram Ebrahimi Armin Skandarzadeh Fatemeh Ziabasharhagh Masoud 《Journal of Thermal Analysis and Calorimetry》2021,145(3):925-953
Journal of Thermal Analysis and Calorimetry - The natural gas entering the liquefaction cycle usually consists of nitrogen, ethane, propane and also heavier hydrocarbons which are economically... 相似文献
66.
Maryam Ebrahimi Jahan Bakhsh Raoof Reza Ojani 《Journal of the Iranian Chemical Society》2018,15(8):1871-1880
In the present paper, we used single-stranded poly-T (100% thymine bases) and poly-C (100% cytosine bases) nucleic acids as DNA probes for selective and sensitive individual electrochemical determination of Hg2+ and Ag+, respectively, on the multi-walled carbon nanotube paste electrodes (MWCNTPEs) using [Fe(CN)6]3?/4? as electroactive labels. In the presence of Hg2+ and Ag+, the probe–Hg2+/Ag+ interactions through T–Hg2+–T and C–Ag+–C complexes formation could cause the formation of a unimolecular hybridized probe. This structure of probe led to its partial depletion from electrode surface and facilitation of electron transfer between [Fe(CN)6]3?/4? redox couple and electrode surface, resulting in the enhanced differential pulse voltammetry (DPV) oxidation current of [Fe(CN)6]3?/4? at the probe-modified electrode surface. We applied the difference in the oxidation peak currents of [Fe(CN)6]3?/4? before and after Hg2+/Ag+–DNA probe bonding (?I) for electrochemical determination of these heavy metal ions. Detection limits were 8.0?×?10?12 M and 1.0?×?10?11 M for Hg2+ and Ag+ ions determination, respectively. The biosensors were utilized to determine the weight percent of toxic metals, i.e., silver and mercury in dental amalgam filling composition. The results of their practical applicability in analysis of the amalgam sample were satisfactory. 相似文献
67.
Maryam Mohebbi Peyman Salehi Morteza Bararjanian Samad N. Ebrahimi 《Journal of the Iranian Chemical Society》2018,15(1):47-53
In this paper, synthesis of two derivatives of noscapine and their application as organocatalysts in the asymmetric addition of diethylzinc to aromatic aldehydes is reported. The first catalyst (2) was synthesized by the reduction of lactone ring of noscapine to form the corresponding diol, and the second one (3) was prepared by tert-butyl dimethyl silylation of the primary hydroxyl group of 2. Excellent yields and high ees up to 95% were obtained by using 3 as the catalyst. To the best of our knowledge, this is the first report on the application of lactone ring opened noscapinoid compounds as organocatalysts in asymmetric reactions. 相似文献
68.
Maryam Ataeefard Siamak Moradian Mojtaba Mirabedini Morteza Ebrahimi Saeed Asiaban 《Plasma Chemistry and Plasma Processing》2008,28(3):377-390
The surface of a LDPE was modified by Ar, O2, N2, CO2 gaseous plasma. The changes in surface morphology and surface wettability were investigated using AFM and SEM. The surface
chemical changes of LDPE were also characterized by FTIR-ATR. The SEM and AFM results demonstrated variable changes in surface
roughness for different types of plasma gas used, the changes being more for the Ar and N2 plasma treatments. Considering the nature of the LDPE film, XRD studies were carried out to determine changes in the percentage
crystalinity. The results showed that all low pressure O2, Ar, N2, CO2 gas plasmas improved the wettability of LDPE films. Contact angles decreased significantly depending on the discharge powers
and exposure times. Surface morphology was also found to vary with plasma discharge powers, exposure times, and the type of
gas being used. Ar and N2 gas plasmas in general produced more superior results. 相似文献
69.
M. Mazloum Ardakani P. Ebrahimi M. R. Mansournia 《Russian Journal of Electrochemistry》2008,44(9):1065-1072
A new salicylate-selective electrode based on the complex (2,3;6,7;10,11;14,15-tetraphenyl-4,9,13,16-tetraoxo-1,5,8,12-tetraazacyclohexadecane)
copper(II) [CuL] as the membrane carrier was developed. The electrode exhibits a good Nernstian slope of −60.9 ± 1.0 mV/decade
and a linear range from 1.0 × 10−6 to 1.0 × 10−1 M for salicylate. The detection limit is 5.0 × 10−7 M. The electrode has a fast response time (5–15 s) and can be used for more than three months. The selective coefficients
were determined by the fixed interference method (FIM) and separate solution method (SSM). The salicylate-selective electrode
could be used in the pH range 3.5–10.5. It was employed as an indicator electrode for direct determination of salicylate in
pharmaceutical samples.
Published in Russian in Elektrokhimiya, 2008, Vol. 44, No. 9, pp. 1147–1154.
The text was submitted by the authors in English. 相似文献
70.
A peptide-modified electrode array with a different peptide on each electrode is compared with a single electrode modified with many peptides for the voltammetric measurement of concentrations of Cu(2+), Cd(2+) and Pb(2+) in solution. The single gold electrode was modified simultaneously with peptides Gly-Gly-His, glutathione and angiotensin I each coupled to thioctic acid, and thioctic acid itself, and the calibration of mixtures of ions was compared with previously published data from an array of four sensors each with an individual modification. Calibration at the multi-peptide single-electrode sensor was by two-way partial least squares (voltammetric current measured with variables 'sample' x 'potential') and for the electrode array by three-way NPLS1 ('sample' x 'potential' x 'electrode'). The advantage of designing experiments to yield multi-way data is demonstrated and discussed. 相似文献