JBCS

This paper presents a simple method for the determination of K in silicate rocks by flame atomic emission spectrometry.

The silica from rice husk ash and the sludge from a water treatment plant when inserted in kaolinite clay provide an increase on vitreous phases as mulite and cristobalite in ceramic plates generating a high mechanical and thermal resistance.

Biofilms prepared by the casting technique (CH, CHG1 and CHG2); measurement of hardness and elastic modulus by linear regression of the contact angle to assess glycerol influence over the wettability and flexibility of biofilms.

Nb₂O₅ (NbPC), Al₂O₃ (AlPC) and Nb₂O₅/Al₂O₃ (NbAlPC) as alternative pretreatment for carbon steel AISI 1005 coating systems and subsequent analysis by Electrochemical Impedance.

Twenty-nine compounds were revealed by GC-MS and UFLC-DAD-MS/MS in the leaves of Eugenia florida as well as their antioxidant and cytotoxic activities.

Formation shceme of Zn(II) complexes with 8-HQ derivatives with substituents N-acyl-hidrazone type substituents and two chloros

Ananas comosus crown was applied for water-based pretreatment at moderate temperatures and enzymatic hydrolysis and fermentation experiments for ethanol and briquettes production.

Spectral changes due to the isomerization of mercury dithizonate(II) in PMMA at 298 K.

Immobilization of HRP on sugarcane bagasse by physical adsorption (ADS) and covalent bond (LC) on activated support by 2.5% (v/v) glutaraldehyde (GA).

Filmogenic solution was obtained by stirring the lemon essential oil on the Turrax stirrer and adding gelatin powder in the nanoemulsion to form the films.

The Velhas River contains high amounts of arsenic and metals in water and sediment samples. BCR method was used to investigate its bioavailability in the sediment. All sediments samples presented As and metals associated with easily mobilized fractions.

Antinociceptive potential of the essential oil obtained from fresh Myrcia rostrata DC. leaves evidenced by the reduction in the number of abdominal writhes induced by acetic acid in mice.

The presence of selected metals in tissues of G. cruentata can represent a potential human health risk to the consumer.

This study shows toxicity results of commercial iron oxide nanoparticles.

Soil substrates must exhibit physical and chemical properties in such way that a high capacity to supply the nutritional demand can be guaranteed, taking into account environmental standards.

Differential scanning calorimetry (DSC) was demonstrated to be a helpful tool to determine the light crude oil (LCO) fraction in biodiesel/LCO blends. DSC results were validated with nuclear magnetic resonance (NMR).

Hydrometallurgical process for printed circuit boards from cell phones using HF + oxidant mixtures under mild experimental conditions. Lead and noble metals were recovered from the insoluble matter.

Metal-Organic Frameworks (MOFs) are a class of porous inorganic solids, in a borderline area between coordination chemistry and material science. Recent research progress in synthesis and potential environmental applications are discussed in this paper.

Acetaminophen or paracetamol is a simplified chemical structure of aniline derivatives and it is used as analgesic agent. Several modifications in its structure particularly on electronic and solubility parameters were performed, seeking the development of safer derivatives.

This review covers some recent work by using Nickel catalysis. In this context, challenged organic transformations, synthetic applications and mechanism investigations are described.

Low-cost flow analysis system: the peristaltic pump and the photometer developed in this work allow the implementation of practical disciplines, such as molecular absorption spectrophotometry and flow analysis system in undergraduate chemistry courses.

Based on spectrophotometry, Ellman's assay correlates activity of cholinesterases with Beer's Law. In absence of an organophosphorus inhibitor, formation of thiol chromophore leads to higher absorbance, which means high activity.

Factorial design: use of free software and videos for better data interpretation.

Alluvial gold mining dredge on the Madeira river. The gold extracted by the dredges is taken to the city of Porto Velho for commercialization, where the its smelting and Hg exposure occurs in the atmosphere of specialized stores.

This study aimed to identify cadmium in low-cost jewelry from China. In the qualitative test, sulfide was used as precipitating agent. Quantification of Cd²⁺ was performed by atomic absorption spectrometry. The content of Cd was ~ 30% (w/w) in one of the investigated pieces.

Methods for biofuel analysis, a topic with relevant socio-economic impact were discussed and compared to help students to gain insight into transesterification mechanism, an important example of acyl-transfer reactions.

The use of case resolution on the reduction of sugar content in processed natural juices for the training of future professionals of Chemistry.

Microwave-assisted synthesis of umbelliferone (7-OH-coumarin) carried out in a domestic microwave oven. Observation of its fluorescence and deprotonation in basic conditions under UV-365 nm lamp.

Students using mass spectrometry to check if the oils were adulterated with soybean oil. An investigative approach to learning mass spectrometry and other fundamental concepts of chemistry.

In this article we discuss the space of Chemistry in Brazilian science centers and museums through a documental survey conducted by telephone, mail and analyzing the websites of those places.

Top Figure: Potential energy for A ⇆ B reaction. Bottom Left Figure: Transitions between states A and B. (i) Ehrenfest urn model (Urns A and B) randomly defines the collision between molecules; (ii) Monte Carlo method (P_AB and PP_BA: Metropolis Update) defines the transition probabilities. Bottom Right Figure: A tipical results for 10² samples.