Analytical chemistry
Morteza Motahharinia; Hassan Ali Zamani; Hassan Karimi Maleh
Abstract
In the present study, ZnO nanoparticle doped with Pd (ZnO-Pd) using one simple chemical precipitation method has been synthesized and characterized by different characterization methods. The synthesized nanoparticle presented a nano-size spherical shape with d
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In the present study, ZnO nanoparticle doped with Pd (ZnO-Pd) using one simple chemical precipitation method has been synthesized and characterized by different characterization methods. The synthesized nanoparticle presented a nano-size spherical shape with d
Analytical chemistry
Ranjhan Junejo; Shahabuddin Memon; Ismail Murat Palabiyik
Abstract
Water might be contaminated by different metal ions, resulting in different water-borne diseases in human and aquatic life. This research study aimed at synthesizing the diethylamine functionalized calix[4]arene based silica (DFCS) resin for the effective removal of heavy metals such as Cd2+, Pb2+, and ...
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Water might be contaminated by different metal ions, resulting in different water-borne diseases in human and aquatic life. This research study aimed at synthesizing the diethylamine functionalized calix[4]arene based silica (DFCS) resin for the effective removal of heavy metals such as Cd2+, Pb2+, and Hg2+ from water. The DFCS resin was characterized using the FTIR spectroscopy and SEM techniques. The efficiency of the DFCS resin for the removal of metal ions was evaluated by performing equilibrium studies under the optimized conditions. Moreover, the experimental data were subjected to isotherm models; however, the Freundlich model was best-fit one as compared to the Langmuir model. The energy calculated from the D-R model was 10.3, 9.7 and 9.2 KJ/mol for Cd2+, Pb2+, and Hg2+,respectively, suggesting that the ion exchange process is involved. The thermodynamic values revealed that the reaction is spontaneous and exothermic, following the pseudo second-order kinetic model equation.
![Efficient adsorption of heavy metal ions onto diethylamine functionalized calix[4]arene based silica resin](data/ecc/coversheet/501587187473.png)
Analytical chemistry
Esmat Shojaei; Mahboubeh Masrournia; Ali Beyramabadi; Hossein Behmadi
Abstract
Chromium has been widely applied in industrial of pigment, stainless steel and electroplating and tanning procedure that enters the water sources. In this work, a simple and reproducible potentiometric sensor was developed for the determination of Cr(III) ions in real solid samples. For this purpose, ...
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Chromium has been widely applied in industrial of pigment, stainless steel and electroplating and tanning procedure that enters the water sources. In this work, a simple and reproducible potentiometric sensor was developed for the determination of Cr(III) ions in real solid samples. For this purpose, a new Schiff base (4-((E)-(2-amino-4 chlorophenylimino) methyl) -5-(hydroxymethyl)-2-methylpyridin-3-ol) were synthesized based on a chemical methods and utilized as a novel and sensitive ionophore for the preparation of Cr(III)-carbon paste electrode. Percentage of carbon paste electrode composition including, graphite powder, ionophore, paraffin oil as a binder, and graphene oxide(GO), was optimized with a chemometric approach using a central composite design method. The optimum percentage of ionophore and nanomaterial in the electrode was obtained 15%w/w. The predicted slope by the computational method and the obtained slope by the experimental method for the proposed sensor was not significantly different. The sensor was linear in the range of 1×10-10- 1×10-2 M for the determination of Cr(III).The effects of other parameters such as pH, response time, lifetime, and interfering ions were studied with one factor at the time method in the optimal composition of the sensor. Proper range of pH, lifetime and response time were acquired 3.5-9.0, 8 weeks and 10 s, respectively. The essential advantages of the proposed sensor were the suitable linear range, a wide range of pH, proper sensor stability, and fast response for the Cr(III) determination. Finally, the analytical application of prepared sensor evaluated to determine Cr(III) in waste and tap water samples.
Analytical chemistry
Sareh Sadat Moshirian-Farahi; Hassan Ali Zamani; Mohamadreza Abedi
Abstract
A high sensitive electroanalytical-based sensor for determination of isoprenaline was fabricated by modification of carbon paste electrode (CPE) by NiO-Pt-Pd/CNTs composite as conductive mediator and n-hexyl-3-methylimidazolium hexafluoro phosphate (NHIHP) as conductive binder. The NHIHP/NiO-Pt-Pd/CNTs/CPE ...
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A high sensitive electroanalytical-based sensor for determination of isoprenaline was fabricated by modification of carbon paste electrode (CPE) by NiO-Pt-Pd/CNTs composite as conductive mediator and n-hexyl-3-methylimidazolium hexafluoro phosphate (NHIHP) as conductive binder. The NHIHP/NiO-Pt-Pd/CNTs/CPE was improved the oxidation signal of isoprenaline ⁓3.47 times and reduced oxidation over-potential of drug ⁓180 mV. The pH investigation confirmed that redox behavior of isoprenaline is depended of pH solution with equal value of electron and proton in redox mechanism. The NHIHP/NiO-Pt-Pd/CNTs/CPE was successfully used for determination of isoprenaline in the concertation range 0.003-300 µM with detection limit 0.9 nM by square wave voltammetric method. The standard addition results showed powerful ability of NHIHP/NiO-Pt-Pd/CNTs/CPE as an electroanalytical tool for determination of isoprenaline in the pharmaceutical and clinical samples with recovery data 98.76-105.06%.
Analytical chemistry
Amin Amraei; Afshin Akbari Dehkharghani
Abstract
Aggregation of solid particles in the drilling fluid has adverse effects on the drilling performance, including blocking drilling pipe, reducing fluid lubrication, and the blowout action. The purpose of this study was to prepare a solution for breaking the adhesion forces between the suspended solids ...
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Aggregation of solid particles in the drilling fluid has adverse effects on the drilling performance, including blocking drilling pipe, reducing fluid lubrication, and the blowout action. The purpose of this study was to prepare a solution for breaking the adhesion forces between the suspended solids and drilling fluid molecules. To investigate the effect of the ultrasonic waves on the separation of solid particles from reversed emulsion fluid, in vitro studies were conducted. Drilling mud was prepared in the form of different samples and the samples were then irradiated with ultrasonic waves for 2, 5, and 10 min and the intensities of 50, 100, and 150 W/m2. To evaluate the stability of the emulsions and the efficiency of the separation process, caliper (volumetric) and density measurement methods were utilized. The results revealed increased time and intensity of the ultrasonic radiation separates the phases and fine particles from the emulsion, and also increased the stability of reversed emulsion. The increased radiation time and intensity did not have any effect on the drilling mud and only delayed the optimal operation time and energy consumption.
Analytical chemistry
Mohammad Reza Aflatoonian; Somayeh Tajik; Behnaz Aflatoonian; Mehri-Saddat Ekrami-Kakhki; Reza Alizadeh
Abstract
Electrochemical behaviors of epinephrine and acetylcholine were investigated, using cyclic voltammetry, on the Ag-ZnO modified screen-printed electrode (Ag-ZnO/SPE). Ag-ZnO nanoplates showed excellent electrocatalytic activity toward the oxidation of epinephrine and acetylcholine compared with bare SPE ...
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Electrochemical behaviors of epinephrine and acetylcholine were investigated, using cyclic voltammetry, on the Ag-ZnO modified screen-printed electrode (Ag-ZnO/SPE). Ag-ZnO nanoplates showed excellent electrocatalytic activity toward the oxidation of epinephrine and acetylcholine compared with bare SPE in 0.1 M PBS. Under the optimized experimental conditions, a linear response obtained in the range of 0.13 to 450.00 μM with detection limit of 0.04 μM for epinephrine. Ag-ZnO/SPE exhibits good stability, reproducibility and repeatability, and the method has been successfully applied for detection of epinephrine and acetylcholine in their pharmaceutical and biological samples with satisfactory recovery.
