A promising electrochemical sensing platform based on copper nanoparticles-decorated polymer in carbon nanotube electrode for monitoring methimazole

In this paper, a novel and convenient electrochemical sensor for detection of methimazole (MMI) by differential pulse voltammetry is presented. This sensor was fabricated by dripping well-dispersed MWCNTs onto glassy carbon electrode (GCE) surface, and then poly-l-Arg (P-L-Arg) film was deposited on the electrode. Finally, Cu nanoparticles (CuNPs) were electrochemically deposited on the resulting film by using cyclic voltammetry to prepare CuNPs-P-L-Arg/MWCNTs/GCE. The surface morphology of the electrodes has been studied by scanning electron microscopy. Studies reveal that the irreversible oxidation of MMI was highly facile on CuNPs-P-L-Arg/MWCNTs/GCE. The dynamic detection range of this sensor to MMI was 5.2–50 µM, with the detection limit of 2 µM. A new voltammetric method for determination of MMI was erected and shows good sensitivity and selectivity, very easy surface update and good stability. The analytical application of the modified electrode is demonstrated by determining MMI in biological fluids (serum).     

Application of SBA-Pr-SO<Subscript>3</Subscript>H in the synthesis of 2,3-dihydroquinazoline-4(1<Emphasis Type="Italic">H</Emphasis>)-ones: characterization,UV–Vis investigations and DFT studies

An efficient one-pot synthesis of 2,3-dihydroquinazoline-4(1H)-one derivatives 4a–l is described using SBA-Pr-SO₃H as a heterogeneous acid catalyst. The present methodology resulted in various derivatives of 2,3-dihydroquinazoline-4(1H)-one in good yield via a three-component reaction of isatoic anhydride, aldehydes and ammonium acetate. SBA-Pr-SO₃H played a significant role as an efficient mesoporous catalyst due to its pore size of 6 nm. Additionally, UV–Vis spectrum of the products was studied in order to investigate their application as UV absorbers.     

Synthesis of 2-mercaptobenzothiazole/magnetic nanoparticles modified multi-walled carbon nanotubes for simultaneous solid-phase microextraction of cadmium and lead

This study describes the successful sequential modification of multi-walled carbon nanotube (MWCNT) by Fe₃O₄ magnetic nanoparticles and 2-mercaptobenzothiazole (MBT) followed by its application as a novel sorbent for simultaneous magnetic solid phase microextraction of lead and cadmium. Fourier transform infrared spectroscopy and scanning electron microscopy were employed to confirm the chemical surface modification of the MWCNT. The ions retained on the 2-MBT/magnetic nanoparticles modified MWCNTs were eluted with 1.0 mL of nitric acid (0.8 mol L^?1) in methanol solution and determined by the flame atomic absorption spectrometry. All parameters affecting the extraction condition were thoroughly investigated and optimised. Under the optimised condition preconcentration factor of 150.0, enhancement factors of 149.0 and 149.2 and limits of detection of 0.21 and 0.01 µg L^?1 were achieved for lead and cadmium, respectively. Using the prepared magnetic nanocomposite, the possible interference of other common ions associated with lead and cadmium determination was effectively avoided and the method was successfully applied to the simultaneous determination of the target ions in various environmental water samples.     

Second comment on: “The effect of pressure on morphological features and quality of synthesized graphene” [Res Chem Intermed DOI 10.1007/s11164-016-2594-8]

Research on Chemical Intermediates - Alipour et&nbsp;al. studied the effect of pressure on the morphological characteristics and quality of synthesized graphene based on scanning electron...     

Experimental Investigation on Upgrading of Lignin‐Derived Bio‐Oils: Kinetic Analysis of Anisole Conversion on Sulfided CoMo/Al2O3 Catalyst

Kinetics of the hydroprocessing of anisole, a compound representative of lignin‐derived bio‐oils, catalyzed by a commercial sulfided CoMo/Al₂O₃, was determined at 8–20 bar pressure and 573–673 K with a once‐through flow reactor. The catalyst was sulfided in an atmosphere of H₂ + H₂S prior to the measurement of its performance. Selectivity‐conversion data were used as a basis for determining an approximate, partially quantified reaction network showing that hydrodeoxygenation (HDO), hydrogenolysis, and alkylation reactions take place simultaneously. The data indicate that these reactions can be stopped at the point where HDO is virtually completed and hydrogenation reactions (and thus H₂ consumption) are minimized. Phenol was the major product of the reactions, with direct deoxygenation of anisole to give benzene being kinetically almost insignificant under our conditions. We infer that the scission of the C_methyl–O bond is more facile than the scission of the C_aromatic–O bond, so that the HDO of anisole likely proceeds substantially through the reactive intermediate phenol to give transalkylation products such as 2‐methylphenol. The data determine rates of formation of the major primary products. The data show that if oxygen removal is the main processing goal, higher temperatures and lower pressures are favored.     

Palladium–S‐propyl‐2‐aminobenzothioate immobilized on Fe3O4 magnetic nanoparticles as catalyst for Suzuki and Heck reactions in water or poly(ethylene glycol)

A moisture‐ and air‐stable heterogenized palladium catalyst was synthesized by coordination of palladium with S‐propyl‐2‐aminothiobenzamide supported on Fe₃O₄ magnetic nanoparticles. The prepared nanocatalyst was characterized using Fourier transform infrared, energy‐dispersive X‐ray and inductively coupled plasma atomic emission spectroscopies, X‐ray diffraction, vibrating sample magnetometry, transmission and scanning electron microscopies, dynamic laser scattering and thermogravimetric analysis. This catalyst could be dispersed homogeneously in water or poly(ethylene glycol) and further applied as an excellent nano‐organometal catalyst for Suzuki and Heck reactions. The catalyst was easily separated with the assistance of an external magnet from the reaction mixture and reused for several consecutive runs without significant loss of its catalytic efficiency or palladium leaching. The leaching of catalyst was examined using hot filtration and inductively coupled plasma atomic emission spectroscopy. Also, the effects of various reaction parameters on the Suzuki and Heck reactions are discussed. Copyright © 2016 John Wiley & Sons, Ltd.     

Chemical Composition of Pentanema kurdistanicum Essential Oil

Chemistry of Natural Compounds -