Sample pretreatment technology plays a vital role in the analysis of complex samples and is key to the entire analytical process. Its main purpose is to separate the substance to be measured from the sample matrix or interfering substances in the sample and to achieve a state in which the instrument can be analyzed and detected. Traditional sample pretreatment techniques include liquid-liquid extraction, liquid-solid extraction, precipitation separation, solvent volatilization-rotary evaporation, filtration, and centrifugation.
View Article and Find Full Text PDFDevelopment of novel porous materials for efficient adsorption and removal of environmental pollutants from aqueous solution is of great importance and interest in environmental science and chemistry. Herein, we reported a facile synthesis of recyclable magnetic carbonaceous porous composite derived from iron-based metal-organic framework MIL-100(Fe) for superior adsorption and removal of malachite green (MG) from aqueous solution. Because of large surface area and high porosity, the synthesized magnetic carbonaceous porous material presented a superior adsorption capacity of 2090 mg g for MG.
View Article and Find Full Text PDFZinc oxide is regarded as a promising candidate for application in photoelectrochemical water oxidation due to its higher electron mobility. However, its instability under alkaline conditions limits its application in a practical setting. Herein, we demonstrate an easily achieved wet-chemical route to chemically stabilize ZnO nanowires (NWs) by protecting them with a thin layer Fe O shell.
View Article and Find Full Text PDFGraphitic carbon nitride (g-CN) has been widely studied as a metal-free photocatalyst, leading to some excellent results; however, the rapid recombination of photogenerated charge carriers substantially limits its performance. Here, we establish two types of g-CN-based heterojunction (type II and nonmediator assisted Z-scheme) photoanodes on a transparent conducting substrate via coupling with rod-like and nanoparticulate WO, respectively. In these composites, g-CN film grown by electrophoretic deposition of exfoliated g-CN serves as the host or guest material.
View Article and Find Full Text PDFTo overcome tough conditions currently used for the preparation of nanostructured hematite films on a conducting substrate, a rational and easy method of chemical etching involving Fe release and material growth in the presence of OH has been developed. By carefully tuning the parameters influencing the morphologies of hematite, including the synthetic procedure, the concentration of etching solution, temperature, etching time and the morphology controlling surfactant, hematite films grown on iron foil with various morphologies (e.g.
View Article and Find Full Text PDFIn this study, an electrochemical sensor of nitro aromatic compound based on three-dimensional porous Pt-Pd nanoparticles (Pt-Pd NPs) supported by reduced graphene oxide (rGO) nanosheets-multiwalled carbon nanotube (CNTs) nanocomposite (marked as Pt-Pd NPs/CNTs-rGO) was investigated for the first time. This hybrid nanocomposite has been prepared via a facile and versatile hydrothermal synthetic strategy while its structure and property are evaluated by X-ray diffraction (XRD), transmission electron microscopy (TEM) and electrochemical impedance spectroscopy (EIS). The result shows that 3D porous Pt-Pd NPs/CNTs-rGO nanocomposite has a large specific surface area of 326.
View Article and Find Full Text PDFIn this paper, coenzyme Q10 (Ubiquinone, CoQ10) was used for the first time as a transducer to construct electrochemical biosensor for effectively detecting γ-L-glutamyl-L-cysteinyl-glycine (glutathione, GSH). CoQ10 modified electrode was fabricated by attaching its gel mixed with multi-walled carbon nanotubes (MWNTs)/ionic liquid (IL). In the optimum conditions, based on the increasing of reduction peak current of CoQ10 caused by GSH through voltammetric technology, it was found that the peak current of CoQ10 was linear with the concentration of GSH in the range from 4.
View Article and Find Full Text PDFActa Crystallogr Sect E Struct Rep Online
February 2013
The title compound, C(28)H(38)Br(2)N(2), is centrosymmetric with the mid-point of the central C-C bond of the butyl group located on an inversion center. The terminal benzene ring is approximately perpendicular to the central 1,4-diaza-butadiene mean plane [dihedral angle = 78.23 (3)°].
View Article and Find Full Text PDFAn efficient and direct protocol for the preparation of amidoalkylnaphthols employing a multi-component, one-pot condensation reaction of 2-naphthol, aromatic aldehydes and acetamide or benzamide in the presence of graphite supported perchloric acid under solvent-free conditions is described. The thermal solvent-free procedure offers advantages such as simple work-up, shorter reaction times and higher product yields, and the catalyst exhibited remarkable reactivity and can be recycled.
View Article and Find Full Text PDFBeing the largest family of cell surface receptors, G-protein-coupled receptors (GPCRs) are among the most frequent targets. The functions of many GPCRs are unknown, and it is both time-consuming and expensive to determine their ligands and signaling pathways by experimental methods. It is of great practical significance to develop an automated and reliable method for classification of GPCRs.
View Article and Find Full Text PDFAbout 20%-30% of genome products have been predicted as membrane proteins, which have significant biological functions. The prediction of the amount and position for the transmembrane protein helical segments (TMHs) is the hot spot in bioinformatics. In this paper, a new approach, maximum spectrum of continuous wavelet transform (MSCWT), is proposed to predict TMHs.
View Article and Find Full Text PDFBackground: The high herbicidal activities of [1,2,4]triazolo[1,5-c]pyrimidine and 2H-1,2,4-thiadiazolo[2,3-a]pyrimidine derivatives suggested the development of new fused heterocyclic compounds for application as herbicides.
Results: Three series of pyrimidinyl-substituted thioureas (4) and amides (5, 6) were synthesized, and the typical crystal structure of a 2H-1,2,4-thiadiazolo[2,3-a]pyrimidine derivative (5a) was determined by X-ray diffraction. All the compounds were tested for herbicidal activity against selected weeds.