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31.
Sedaghat Marjan Vahid Behrouz Aber Soheil Rasoulifard Mohammad H. Khataee Alireza Daneshvar Nezamalddin 《Research on Chemical Intermediates》2016,42(2):855-868
Research on Chemical Intermediates - The aim of this study was to compare the degradation efficiency (DE%) of imidacloprid as a model pesticide by electro-Fenton (EF) and photoelectro-Fenton... 相似文献
32.
Ethylene glycol was used as an efficient and recoverable medium for the reaction of diazoles with aryl iodides and aryl bromides in the presence of CuCl2 as the catalyst and K2CO3 as the base. Consequently, imidazole, benzimidazole, and pyrazole reacted readily under microwave irradiation to give good to excellent yields of their corresponding N-arylated products in relatively short time periods. Apparently, ethylene glycol plays a dual role by activating the catalyst and also providing a homogenous medium for the processes. The reaction medium consisting of the solvent, the base, and the copper salt was recovered and reused successfully in the next several reactions. 相似文献
33.
The surfaces of polyethylene terephthalate (PET) obtained by irradiation with a CO2 pulsed laser in air were studied. The complicated microstructures using various laser wavelengths were observed by scanning electron microscopy (SEM). The changes in chemical and physical properties of the irradiated PET surface were investigated by attenuated total reflectance infrared spectroscopy (ATR-FTIR) and contact angle measurements. ATR-IR spectrum showed that the crystallinity in the surface region decreased due to laser irradiation. The water drop contact angle also decreased with increasing of laser pulses. The density of peroxides formed on the irradiated PET surface were determined by iodide method. 相似文献
34.
S. L. Chin H. L. Xu Q. Luo F. Théberge W. Liu J. F. Daigle Y. Kamali P. T. Simard J. Bernhardt S. A. Hosseini M. Sharifi G. Méjean A. Azarm C. Marceau O. Kosareva V. P. Kandidov N. Ak?zbek A. Becker G. Roy P. Mathieu J. R. Simard M. Chateauneuf J. Dubois 《Applied physics. B, Lasers and optics》2009,95(1):1-12
All matters in the path of filaments induced by an intense femtosecond laser pulse propagating in air could be fragmented
and result in the emission of characteristic fluorescence spectra from the excited fragments. The fluorescence spectra exhibit
specific signatures (fingerprints) that can be used for the identification of various substances including chemical and biological
species. In this paper, we present an overview of the recent progress in our laboratory concerning the “remote” sensing of
chemical and biological agents/pollutants in air using filamentation-induced nonlinear fluorescence techniques. 相似文献
35.
JPC – Journal of Planar Chromatography – Modern TLC - High-performance liquid chromatography (HPLC) has been the most popular choice for analysis of tamoxifen citrate. In this study,... 相似文献
36.
Babak Mokhtarani Ali Sharifi Hamid Reza Mortaheb Mojtaba Mirzaei Morteza Mafi Fatemeh Sadeghian 《The Journal of chemical thermodynamics》2009,41(12):1432-1438
Densities and viscosities of 1-butyl-3-methylimidazolium nitrate [Bmim][NO3], and its binaries with alcohol (ethanol, 1-propanol, or 1-butanol) were measured at different temperatures. The densities and viscosities of pure ionic liquid were correlated successfully by empirical equations. The Vogel–Fulcher–Tammann equations can fit the experimental data of viscosities for pure IL. Excess molar volume and viscosity deviations were calculated for the binaries. The excess molar volumes have negative deviations from the ideal solution. 相似文献
37.
Abbas Sharifi Saber Yekani Motlagh Homayoun Badfar 《International Journal of Computational Fluid Dynamics》2013,27(4-5):248-259
ABSTRACTIn this paper, effects of two wires magnetic field on heat transfer and biomagnetic fluid flow in an aneurysm have been investigated using the ferrohydrodynamics model. Using the finite volume method and the SIMPLE algorithm, the governing equations have been discretised. Simulations have been carried out for both conditions of wires in the same and opposite directions and different magnetic numbers of 41 and 82. Results show that the magnetic field causes a decrease in heat transfer of blood flow towards the walls. Moreover, major energy loss or pressure drop, arising from mean wall shear stress, decreases but local or minor energy loss, arising from aneurysm vortexes, increases. Furthermore, risk factors of aneurysm rupture is decreased under the effect of the magnetic field. The effective contact surface between drug-coated magnetic nanoparticles and the aneurysm tissue may increase and residence time of drug on the cells of the region would decrease. 相似文献
38.
Ali Nemati Hayati Mohammad Mehdi Ahmadi Soheil Mohammadi 《Transport in Porous Media》2012,93(1):13-27
Analytical solution of shock wave propagation in pure gas in a shock tube is usually addressed in gas dynamics. However, such
a solution for granular media is complex due to the inclusion of parameters relating to particles configuration within the
medium, which affect the balance equations. In this article, an analytical solution for isothermal shock wave propagation
in an isotropic homogenous rigid granular material is presented, and a closed-form solution is obtained for the case of weak
shock waves. Fluid mass and momentum equations are first written in wave and (mathematical) non-conservation forms. Afterwards
by redefining the sound speed of the gas flowing inside the pores, an analytical solution is obtained using the classical
method of characteristics, followed by Taylor’s series expansion based on the assumption of weak flow which finally led to
explicit functions for velocity, density and pressure. The solution enables plotting gas velocity, density and pressure variations
in the porous medium, which is of high interest in the design of granular shock isolators. 相似文献
39.
Small angle neutron scattering (SANS) is used to analyze the structure of opals and inverse opals made by the capillary deposition method. We show that there is no deformation in special lattice directions such as the growth direction and the support plane direction. However, effects of twinning of the dense-packed structure and plane-like lattice perturbations have been observed. The latter appear as linear surface disturbances. We propose a model with an anisotropic distribution of stacking faults which delivers the different peak intensities in the neutron diffraction pattern. The rocking curves show that small perfect crystal parts are aligned better than ±3° and ±11° for the opals and inverse opals, respectively. 相似文献
40.
Leila Bakhtiyari Fereshteh Moghimi Seyed Soheil Mansouri Ali Farsi Masoud M. Malek-Shah 《Research on Chemical Intermediates》2012,38(3-5):965-982
The production of metal concentrates during mineral processing of ferrous and non-ferrous metals involves a variety of highly corrosive chemicals which deteriorate common mild steel as the material of choice in the construction of such lines, through rapid propagation of localized pitting in susceptible parts, often in sensitive areas. This requires unscheduled maintenance and plant shut down. In order to test the corrosion resistance of different available materials as replacement materials, polarization and electrochemical impedance spectroscopy (EIS) tests were carried out. The EIS numerical outputs were then transformed into an equivalent electric circuit using Z-View software, and the predictive behavior was contrasted with actual performance after long-term immersion, depicted through SEM, EDS, XRD and weight change observations. Also, results of pits and cracks, obtained with climax software-enhanced polarization resistance, and reduced capacitance added to much diminished current densities, verified the acceptable performance of CK45 compared with high priced stainless steel substitutes with comparable operational life. Therefore, CK45 can be a suitable alternative in steel constructions which are exposed to super-alkaline and corrosive environments. 相似文献