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61.
Zahra Jafari Chermahini Alireza Najafi Chermahini Hossein A. Dabbagh Behzad Rezaei Neda Irannejad 《Journal of the Iranian Chemical Society》2017,14(7):1549-1556
Di(1H-tetrazol-5-yl)methane is employed as a new electron acceptor group in the synthesis of two metal-free organic dyes containing triphenylamine donor group. Dye-sensitized nanocrystalline TiO2 solar cell (DSSC) applying these novel dyes is constructed for consideration of their photovoltaic properties. The electronic properties of the dyes are also considered with the aid of theoretical calculations. The DSSC constructed from 4-(2,2-di(1H-tetrazol-5-yl)vinyl)-N,N-diphenylaniline (T1) shows a short-circuit photocurrent density of 13.38 mA cm?2, an open circuit voltage of 578 mV, and a fill factor of 0.54, with a resulted solar energy-to-electricity conversion efficiency of 4.18% under simulated 1 sun irradiation (100 mW cm?2). This result reveals that the dye with the di(1H-tetrazol-5-yl)methane anchoring group injects more electrons to the conduction band of TiO2 in comparison with its analogs with single tetrazole ring in their anchoring group. It is found that in spite of a red-shift of the absorption spectrum resulted from the lengthening of the molecule, the dye with two di(1H-tetrazol-5-yl)methane groups gives lower performance than the dye with a single electron acceptor. 相似文献
62.
Khezri Behrooz Maskanati Maryam Zohrevand Bahareh Liyaghati-Delshad Mozhdeh Soltanali Fatemeh 《Structural chemistry》2022,33(2):315-322
Structural Chemistry - This is an analysis report on the use of density functional theory (DFT) to investigate the potentials of pristine and amino acid–functionalized C4B32 borospherenes in... 相似文献
63.
Some properties of pseudoinvex functions, defined by means of limiting subdifferential, are obtained. Furthermore, the equivalence between vector variational-like inequalities involving limiting subdifferential and vector optimization problems are studied under pseudoinvexity condition. 相似文献
64.
Fereshteh Rezaei Nahid Pirhady Tavandashti Ali Reza Zahedi 《Research on Chemical Intermediates》2014,40(3):1233-1247
Polyaniline nanofibers are readily synthesized by bulk polymerization; ammonium per sulphate (APS) is used as oxidizing agent and hydrochloric acid as dopant without any hard or soft templates. A detailed study was conducted on the effect of a variety of synthetic conditions on the size and morphology of the polyaniline nanostructure. These conditions include the concentration of dopant, and the APS-to-aniline and acid-to-aniline molar ratios. The morphology of the nanofibers was confirmed by SEM and TEM. XRD and FT-IR and UV–visible spectroscopy were used for structural characterization of nanofibers. The results showed that not only the microstructure of the polyaniline product, but also other characteristics, for example conductivity, crystallinity, and, more importantly, the efficiency of the process are strongly affected by the synthetic conditions. 相似文献
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66.
Ali A. Ensafi S. Fattahi-Sedeh M. Jafari-Asl B. Rezaei 《Journal of the Iranian Chemical Society》2017,14(5):1069-1078
In this work, thionine (Th) was assembled on the surface of graphene oxide as an electron transfer mediator using diazonium reaction (Th–GO). Then, Th–GO was characterized by different methods such as scanning electron microscopy, transmission electron microscopy, and Fourier transform infrared spectroscopy. Afterward, Th–GO was used for the modification of carbon paste electrode. Several electrochemical methods including cyclic voltammetry, differential pulse voltammetry, and hydrodynamic amperometry were used to investigate the behavior of the modified electrode. Then, the role of the modified electrode for oxidation of nitrite has been studied. For this purpose, the effect of critical experimental parameters including step potential and pulse amplitude (in differential pulse voltammetry technique), applied potential, the rotating speed of the disk (in amperometry technique), and the solution pH was investigated. Under the optimized conditions, the currents were found to be linear with the nitrite concentration in the range 0.05–33.0 and 0.5–800 µmol L?1 with detection limits of 0.02 and 0.2 µmol L?1 using differential pulse voltammetry and hydrodynamic amperometry, respectively. The introduced modified electrode showed good repeatability (RSD% = 3.2) and reproducibility (RSD% = 4.7). This electrochemical sensor was exerted successfully for the determination of nitrite and nitrate in real samples including water and wastewater samples. 相似文献
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69.
The impact of fractional wettability on the production characteristics of a VAPEX process at the macroscale was investigated.
Conventional VAPEX experiments were conducted in a 220 Darcy random packing of glass beads in a rectangular physical model
and n-pentane was used to recover the Cold Lake bitumen from the oil-saturated model in the absence of connate water. The composition
of oil-wet beads in the packed bed was altered from completely water-wet beads to completely oil-wet beads at different proportions
of oil-wet beads mixed with water-wet beads. A substantial increase (about 40%) in the production rate of live oil was observed
during the VAPEX process when the wettability of the porous packing was entirely oil-wet beads. A critical oil-wet fraction
of 0.66 was found for the heterogeneous packing of water-wet and oil-wet beads of similar size distribution. Above this critical
composition, the live oil production rate was not affected by further increase in the proportion of the oil-wet beads. It
is believed that above this critical composition of the oil-wet beads, the crevice flow process is dominated by the continuity
of higher conductivity live oil films between particles through the oil-wet regions. Below this critical composition, the
live oil production rate increased linearly with the fraction of the oil-wet beads in the packing. The oil-wet regions favor
the live oil drainage compared to that of the water-wet regions as they enhance the rate of imbibition of the live oil from
the oil-filled pores to the vacated pores near the nominal VAPEX interface. These two factors enhance the live oil production
rate during the VAPEX process. The solvent content of the live oil, the solvent-to-oil ratio (SOR), and the residual oil saturation
did not correlate strongly with the proportion of the oil-wet beads in the packing. The average solvent content of the live
oil and the residual oil saturation were measured to be 48% by weight and 7% by volume respectively. 相似文献
70.
Aeroelastic analysis of a rotating wind turbine blade using a geometrically exact formulation 总被引:1,自引:0,他引:1
In this paper, an aeroelastic analysis of a rotating wind turbine blade is performed by considering the effects of geometrical nonlinearities associated with large deflection of the blade produced during wind turbine operation. This source of nonlinearity has become more important in the dynamic analysis of flexible blades used in more recent multi-megawatt wind turbines. The structural modeling, involving the coupled edgewise, flapwise and torsional DOFs, has been performed by using a nonlinear geometrically exact beam formulation. The aerodynamic model is presented based on the strip theory, by applying the principles of quasi-steady and unsteady airfoil aerodynamics. Compared to the conventional steady aerodynamic model, the presented model offers a more realistic consideration of fluid–structure interactions. The resulting governing equation, expanded up to the third-order terms, is analyzed by using the reduced-order model (ROM). The ROM is developed by employing the coupled mode shapes of a cantilever blade under free loading condition. The specifications of the 5MW-NREL wind turbine are used in the simulation study. After verifying the ROM results by comparing them with those of the full FEM model, the model is used in additional static, modal and transient dynamics analyses. The results indicate the important effect of geometrical nonlinearity, especially for larger structural deformations. Moreover, nonlinear analyses reveal the important effects of torsion induced by lateral deformations. It is also found that the governing equation is more efficient, and sufficiently accurate, when it is developed by using the second-order kinetic terms, third-order potential terms and the second-order aerodynamic terms together with third-order damping. Finally, the effects of nonlinearities on the flutter characteristics of wind turbine blades are evaluated through frequency and dynamic analyses. 相似文献