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101.
The temporal rheological behavior of FENE and FENE-P models is investigated using the flow in a circular, straight tube. The CONNFFESSIT approach is applied to simulate transient Hagen–Poiseuille flow for different pressure drops and model parameters. The material functions for steady and unsteady flow were extracted and compared with the reported values in the literature when it was available. For the case of the FENE model, where there is no analytical solution, the relationship between model parameters and rheological behavior has been discussed and compared with the FENE-P model. 相似文献
102.
The interaction of Fenitrothion with DNA has been studied using the voltammetric and spectroscopic methods. An irreversible reduction was concluded from the CV data of Fenitrothion. The values of (αn)f=1.91 and (αn)b=2.06 were measured and the reduction process of Fenitrothion was performed with 4 electrons. By using non‐linear regression analysis of CV data, the binding constant, binding site size, and diffusion coefficient for free Fenitrothion (Df) and DNA‐Fenitrothion (Db) were calculated as: 1.03×104, 1.204, 5.2×10?4 and 1.72×10?5, respectively. Also the voltammetric, spectroscopic, thermodynamic and activation energy of DNA‐Fenitrothion complex revealed that the mode of interaction might be partial‐intercalative and complex formation is entropy favored. 相似文献
103.
S.K. Sadrnezhaad Rafi Ali Rahimi Gholamreza Raisali Farhad Foruzanfar 《Journal of Non》2009,355(48-49):2400-2404
Mechanism of removal of lead from silicate glass containing 68.5 wt% PbO by 0.5 N HNO3 was investigated by incorporation of the chemical-analyses/weight-loss data into shrinking-core model (SCM) and minimization of the difference. Scanning electron microscopy (SEM), emission spectrometry with inductively coupled plasma (ICP), X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDS) were used to determine the compositional changes of the lead-silicate glass (LSG) samples. Dual inter-diffusion chemical reaction mechanisms having respective activation energies of 83.49 and 47.80 kJ/mol dominated the deleading process. 相似文献
104.
105.
Semicarbazones,1,1-diacetates and acetals are efficiently converted to their corresponding carbonyl compounds using synergistic effect between KBrO3 and MoO3 in refluxing CH3CN-H20 in good to high yields. 相似文献
106.
Peykani Pejman Hosseinzadeh Lotfi Farhad Sadjadi Seyed Jafar Ebrahimnejad Ali Mohammadi Emran 《Fuzzy Optimization and Decision Making》2022,21(2):197-261
Fuzzy Optimization and Decision Making - Fuzzy data envelopment analysis (FDEA) is one of the most applicable approaches for performance assessment of peer decision making units under ambiguity... 相似文献
107.
Farhad Gharagheizi Mohammad Hossein Keshavarz Mehdi Sattari 《Journal of Thermal Analysis and Calorimetry》2012,110(2):1005-1012
In this study, a simple three-parameter linear model is presented for estimation of flash point (FP) of pure compounds. The parameters of the model contain experimental normal boiling point of the compound and two chemical structure-based parameters. A comprehensive database of FPs containing 1472 pure compounds of various chemical structures was used to develop the model. The squared correlation coefficient and average absolute error of the model calculation results for all of the compounds presented in the database are evaluated to be 0.982 and 7.2?K, respectively. 相似文献
108.
This paper describes a new class of three‐dimensional finite difference schemes for high‐speed turbulent flows in complex geometries based on the high‐order monotonicity‐preserving (MP) method. Simulations conducted for various 1D, 2D, and 3D problems indicate that the new high‐order MP schemes can preserve sharp changes in the flow variables without spurious oscillations and are able to capture the turbulence at the smallest computed scales. Our results also indicate that the MP method has less numerical dissipation and faster grid convergence than the weighted essentially non‐oscillatory method. However, both of these methods are computationally more demanding than the COMP method and are only used for the inviscid fluxes. To reduce the computational cost for reacting flows, the scalar equations are solved by the COMP method, which is shown to yield similar results to those obtained by the MP in supersonic turbulent flows with strong shock waves. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
109.
Farhad Faghihi Naser Mohammadi Majid Haghgoo 《Journal of Polymer Science.Polymer Physics》2010,48(1):82-88
Glass transition characteristics and mechanical wave attenuation of the neat and filled styrene‐butadiene rubber (SBR) containing 10 wt % of rigid monosize polystyrene particles of various diameters from several hundred microns down to several tens of nanometers were investigated by dynamic mechanical thermal analysis, impedance tube, and ultrasonic spectroscopy. The results showed the matrix damping capacity and the breadth of glass transition increase by reducing the size of rigid particles due to the matrix‐particles interfacial area increase as the major governing parameter. Matrix glass transition broadening toward higher temperatures was attributed to the increased dynamic heterogeneity induced by fillers, whereas the damping capacity increase was assigned to contribution of interfacial friction loss mechanism. The proposed postulation was confirmed based on the calculated temperature distribution of the relaxing matrix volume fraction. Sound wave attenuation by the matrix and PS particles filled systems led to a broad absorption peak for the former and appearance of a secondary absorption peak at lower frequencies for the latter. Intensity of this secondary peak was highest for the system containing PS nanoparticles. Finally, ultrasonic attenuation enhanced by the PS particle size to wavelength ratio increase according to αsca ~ (d/λ)0.38 scaling law and declined by replacing the dense particles with larger hollow PS particles. Comparison of the normalized attenuation of the PS particle filled SBR in various mechanical wave attenuation regimes implied low sensitivity to particle size in vibration, mild differentiation in the sound, and finally severe differentiation in the ultrasound regimes. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 82–88, 2010 相似文献
110.