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81.
82.
Jalal Albadi Farhad Shirini Jafar Abasi Nezam Armand Tayebeh Motaharizadeh 《Comptes Rendus Chimie》2013,16(5):407-411
Poly(4-vinylpyridine)-supported copper iodide is reported as a green, efficient and recyclable catalyst for the synthesis of coumarin derivatives by the Pechmann reaction under solvent-free conditions. This catalyst can be recovered by simple filtration and recycled up to eight consecutive runs without any loss of their efficiency. 相似文献
83.
84.
Farhad Gharagheizi Mohammad Hossein Keshavarz Poorandokht Ilani-Kashkouli Nasrin Farahani Kaniki Tumba 《Journal of Thermal Analysis and Calorimetry》2013,114(3):1363-1382
Glass-transition temperature (T g) of ionic liquids (ILs) plays a key role in assessment of their potential for electrolyte application purposes. In this communication, a new group contribution model is presented for the prediction of the T g of 1,3-dialkylimidazolium, a class of ILs, which has great potentialities to serve as electrolyte. To develop this model, the contribution of ILs’ anions and cations is separately considered. This simple model shows a low average relative deviation of 1.94 % for a data set including 109 experimental glass-transition temperature. 相似文献
85.
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
86.
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
87.
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
88.
89.
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
90.
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