Silver nanoparticles effect on Artemia salina and Allium cepa organisms: influence of test dilution solutions on toxicity and particles aggregation.

The objective of this study was to evaluate the effects of AgNPs on Artemia salina and Allium cepa, evaluating the influence of the dilution solutions on the particle behavior. The AgNPs were synthesized by chemical reduction of AgNO (3 and 5 mmol L) with sodium borohydride and stabilized with PVA (polyvinyl alcohol) and CMC (sodium carboxymethyl cellulose). The toxicity of AgNPs was evaluated in Artemia salina (mortality) using Meyer's solution as a diluent and in Allium cepa (chromosomal aberrations) using reconstituted hard water.

Chrysotile asbestos treated with phosphoric acid as an adsorbent for ammonia nitrogen.

The purpose of this study was to find an alternative application for chrysotile asbestos, given that there is a complete structure of extraction and production of this class of serpentine minerals, but its use is banned for many applications. The idea was to obtain a compound that could immobilize phosphate by triggering a reaction between the magnesium oxide and hydroxide contained in the mineral, without causing phosphate leaching. To this end, chrysotile (MgSiO(OH)) was treated with phosphoric acid (HPO) in a molar ratio of 1:3 in an aqueous medium at 85 °C until the solvent evaporated, resulting in two different solid compounds, which were prepared in a similar manner.

A comparative study between Cu(INA)-MOF and [Cu(INA)(HO)] complex for a click reaction and the Biginelli reaction under solvent-free conditions.

The catalytic activity of metal-organic framework Cu(INA) (INA = isonicotinate ion) and the complex [Cu(INA)(HO)] were studied in the Copper-catalyzed Azide-Alkyne Cycloaddition (CuAAC) and Biginelli reaction under solvent-free reaction conditions. The robust, efficient and eco-friendly new method allowed the preparation of a variety of 1,2,3-triazole compounds in good to excellent yields and high selectivity for the 1,4-disubstituted triazole. Moreover, for the Biginelli reaction between aldehydes, ethyl acetoacetate and urea, the corresponding dihydropyrimidinones (DHPMs) were also obtained in satisfactory yields under mild reaction conditions for both catalysts.

SPME fiber coated by arrayed ZNRs for sampling and concentration of polar residual solvents for further analysis using GC FID.

In this work, fused silica coated by arrayed ZNRs were successfully applied as a sorbent for analysis of polar residual solvents in pantoprazole feedstocks. ZnO nanoparticles were produced and deposited on a fused silica surface applying the dip coating technique and hydrothermal growth to synthesize the arrayed nanorods. The ZNRs array fiber coating was characterized by SEM, EDS, XRD, and TGA.

Adsorption of reactive blue BF-5G dye by soybean hulls: kinetics, equilibrium and influencing factors.

The textile industry is known for the high use of chemicals, such as dyes, and large volumes of effluent that contaminate waters, a fact that has encouraged research and improved treatment techniques. In this study, we used unprocessed soybean hulls for the removal of reactive blue BF-5G dye. The point of zero charge of soybean hulls was 6.

ZnO-coated glass fibers for the analysis of trihalomethanes by headspace-solid phase microextraction-gas chromatography.

Li(2)O-ZrO(2)-BaO-SiO(2) glass fibers were produced and their surfaces were coated with zinc oxide. The fibers' surface morphology was examined by scanning electron microscopy and the zinc oxide layer was characterized by mapping the K(α) and L(α) lines of zinc by energy dispersive X-ray spectroscopy. The results indicated that a homogeneous and porous layer of ZnO was formed on the fibers' surface.

Quaternary Ammonium Salts Immobilized on Silica Gel: Exchange Properties and Application as Potentiometric Sensor for Perchlorate Ions.

Ammonium chlorides immobilized on silica gel, SA(+)/Cl(-) and SE(+)/Cl(-), were obtained from silica previously modified with 3-aminopropyltriethoxysilane and N-[3-(trimethoxysilyl)-propyl]ethylenediamine, respectively. Both materials showed potential use as an anion exchanger: they are thermically stable (up to 413 K), achieve equilibrium rapidly in the presence of suitable exchanger ions, and are easily recovered. The exchange capacities observed for SA(+)/Cl(-) and SE(+)/Cl(-) are 0.