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111.
Reactive Violet 5 and its hydrolysis product, which is produced as a side product in the dyeing process, can be determined in an admixture at sub-ppb levels by cathodic stripping voltammetry because the potentials of their azo reduction peaks are separated sufficiently. For both dyes, at intermediate pH values the azo peak is preceded by a complexed -copper reduction peak at a less negative potential, which aids the identification of the dyes. The use of pH 6 EDTA buffer removes the complexed-copper peak, as does the use of an acidic buffer (pH < 3). This unusual use of EDTA as a pH buffer facilitates the determination of mixtures of the dye and its hydrolysis product. 相似文献
112.
Hadi Rezazadeh Alper Korkmaz Mostafa Eslami Javad Vahidi Rahim Asghari 《Optical and Quantum Electronics》2018,50(3):150
The generalized projective Riccati equation method is proposed to establish exact solutions for generalized form of the reaction Duffing model in fractional sense namely, Khalil’s derivative. The compatible traveling wave transform converts the governing equation to a non linear ODE. The predicted solution is a series of two new variables that solve a particular ODE system. Coefficients of terms in the series are calculated by solving an algebraic system that comes into existence by substitution of the predicted solution into the ODE which is the result of the wave transformation of the governing equation. Returning original variables give exact solutions to the governing equation in various forms. 相似文献
113.
Elnaz Marzi Khosrowshahi Habib Razmi Rahim Mohammad-Rezaei Mahdiyeh Hassanpour Khaneghah 《Journal of the Iranian Chemical Society》2018,15(11):2475-2482
In this study, a simple, sensitive and low-cost iodate electrochemical sensor based on graphenized pencil lead electrode (GPLE) modified with Ag nanoparticles (AgNPs) was presented. The GPLE was simply prepared via electrochemical exfoliation of pencil lead electrode (PLE) by applying an optimized potential in acidic media. Afterward, silver nanoparticles were electrochemically deposited on the surface of GPLE using chronoamperometry technique. The fabricated electrode was carefully characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM) techniques. Electrochemical behavior and also the electrocatalytic performance of the modified electrode toward the reduction of iodate were studied in details using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. The fabricated sensor responds efficiently to iodate over the concentration range of 0.05 to 75 mM with a detection limit of 0.017 mM and sensitivity of 0.26 µA µM?1 cm?2. Remarkably enhanced electrocatalytic performance of the modified electrode was ascribed to the synergistic effect of graphene-like nanostructures with high surface to volume ratio, excellent conductivity and also the excessive electrocatalytic behavior of silver nanoparticles. The modified electrode was successfully employed for the determination of iodate in table and sea salt samples. 相似文献
114.
F,Cl, Br Doped Ge44 and Al22P22 Nanocages As Anode Electrode Materials of Li,Na, and K ion Batteries
Surendar A. Munir Ahmed Shepelyuk O. L. Robbi Rahim Meysam Najafi 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2018,92(11):2282-2288
Russian Journal of Physical Chemistry A - In this study, the potential of Ge44 and Al22P22 as anode electrodes of Li-ion, Na-ion, and K-ion batteries were investigated via density functional... 相似文献
115.
Omed S. Q. Yousif Moses Karakouzian Nawzad O. A. Rahim Kamal A. Rashed 《Transport in Porous Media》2017,120(3):643-659
This study investigated the physical clogging of uniformly graded porous media under constant flow rates using natural porous media and suspensions. The porous media selected for this experimental study was a fine-to-medium sandy soil fractioned into thirteen uniformly graded beds: seven unisize beds and six uniform beds. The physical clogging of the beds was studied using two types of silt suspensions as along with two suspension concentrations and three water discharges. It was found that the permeability reduction due to physical clogging \([(K_\mathrm{i} - K_\mathrm{t})/K_\mathrm{i}]\) increased with decreasing \({D}_{15}/{d}_{85}\) ratios until a critical value of \({D}_{15}/{d}_{85}\), after which a surface mat of suspension was formed on the porous media. It was also found that the value of reduced permeability at any time (at any number of pore volumes of injected suspension-laden water), \(K_\mathrm{t}\), is directly proportional to square of \({D}_{15}\) and inversely proportional to \({C}_{\mathrm{u}}\) of the porous media and \({d}_{85}\) of suspensions. The effects of suspension type and flow rates on physical clogging seemed to depend on the size of the pores in the porous media. 相似文献
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A low‐cost and highly effective zinc/THF‐saturated aqueous ammonium chloride has been developed for dehalogenation of arylhalides and alkylhalides in aqueous systems. 相似文献