JBCS

In this study, a simple, portable and low-cost analytical method for the determination of salycilic acid is presented. The reaction between the analyte and Fe^III ions is used for salicylic acid (SA) recognition, and the quantification is based on the color information extracted by digital images.

Quantum computing simulators can provide valuable insights into electronic structures, offering a significant step toward exact simulations using full-fledged quantum computers.

Electrospray ionization-ion trap mass spectrometry (ESI(-)-ITMS) and ultra-performance liquid chromatography coupled with electrospray ionization quadrupole-time-of-flight mass spectrometry (UPLC-ESI-QTOF-MS/MS) analysis of the fractions from leaves of Dipteryx lacunifera led to the annotation of twenty-one polar compounds (1-21). The antioxidant and cytotoxic potential of the ethyl acetate and ethereal fractions was also observed.

Corrosion rate comparison in millimeters per year between the cities of Cubatão, Praia Grande and São Paulo in the following cases: exposed without anode; exposed with anode; buried without anode; buried with anode.

Based on zeolitic imidazolate framework-8 (ZIF-8), Zn-Fe bimetallic ZIF was synthesized. Subsequently, the photocatalytic nitrogen fixation performance of the sample was investigated. The synthesis process of the samples is simple, and they exhibit excellent photocatalytic nitrogen fixation performance.

In this study, the influence of deaeration on the electrochemical behavior of aluminum was investigated using polarization techniques. The advantages of deaeration in assessing localized corrosion on aluminum are addressed.

A portable near-infrared spectrometer (linear variable filter (LVF) used as a dispersive element) was applied to rapidly detect methamphetamine samples on site, and 359 methamphetamine crystal and 187 methamphetamine tablet samples were modeled and analyzed.

Stereoselective synthesis of α-aryl enaminones was developed by TfOH-promoted cascade reactions via 1,3-dipolar cycloaddition of alkyl azides with dibenzylidene ketones, aziridine formation, and 1,2-aryl migration. Starting materials are readily available and TfOH is easy to handle.

An alumina supported NiNb metal oxide prepared from hydrothermal method was successfully applied for ethane oxidative dehydrogenation (ODH) to ethylene. The hydrothermal method led to the feasible formation of active sites over the NiNb sample, which presented the highest selectivity toward ethylene due to the special nature of surface oxygen with low reducible sites.

Compounds 2 and 4 are novel via bromination. Compound 2 has inhibited well against Staphylococcus aureus and Bacillus cereus bacteria with minimal inhibitory concentration (MIC) values of 13.20 and 6.6 µM, respectively, and 2 inhibited stronger than parent compound 1.

Multivariate curve resolution is used to quantify the content of palm oil methyl biodiesel in diesel blends. This tool recovers the pure profiles of analytes in complex mixtures, managing to determine the concentration of the species of interest even in the presence of interferents.

KBiO₃ and BiOCl form the p-n heterojunction that makes the photo-induced electrons and holes efficiently separated and the recombination of electron-hole pairs hindered under visible light. Therefore, the photocatalytic effect can be greatly improved.

By using TiCl₄ as the titanium source, we systematically determined the degree of hydrolysis of Ti⁴⁺ by adding triethanolamine (C₆H₁₅NO₃) dropwise. By collecting solutions at different time points and performing UV spectroscopy analysis, we plotted the Ti⁴⁺ concentration over time. This study not only reveals the hydrolysis behavior of Ti⁴⁺ under different conditions, but also provides a theoretical basis and experimental method for the precise control of the hydrolysis process of Ti⁴⁺. Such research results have important guiding significance for the preparation and application of titanium-based materials.

Comparison of fatty acids and triacylglycerols in human, cow, and goat milk as a basis for supplementation in infant formulas.

A new pelletization proposal allowed, from the solid state synthesis between the clay mineral palygorskite, lignin (paper pulp residue) and WAX^®, the application of the composite in environmental remediation, removing 88.36% of Pb^II ions in 60 min and in batch system.

The reinjection of CO₂ into oil reservoirs as a mitigation project can influence asphaltene molecules. These structures can aggregate, precipitate, and cause several problems in the oil industry.

Vehicles emit air pollutants, such as volatile organic compounds (VOC) and nitrogen oxides, which in the presence of sunlight, lead to the ozone formation. As ozone is the main product, it is a parameter used to control vehicular emission.

By injecting ozone microbubbles, it can effectively remove Fe²⁺ in CO₂-rich mineral water to prevent sediment from occurring during storage and increase shelf life.

Bulk precipitation samples collected at two coastal urban sites (downtown Niterói and APA Guapimirim) in the Metropolitan Region of Rio de Janeiro and at two montane Atlantic Forest (at 400 and 1000 m altitude) areas within Serra dos Órgãos National Park (PARNASO) were investigated for inorganic ions.

Chromium VI is a highly toxic species and must be controlled in organic fertilizers. A simple spectrophotometric method was developed and validated for its determination.

The quartz crystal microbalance (QCM) gas sensor based on polyaniline nanofibers has ultra-sensitive moisture-resistant detection capability for benzene, toluene, ethylbenzene, and xylene (BTEX) vapors.

This graphical abstract shows the ultraviolet-induced visible luminescence (UVL), infrared (IR) images and elemental maps Pb-L, Fe-K and Zn-K obtained in investigation of the painting "Costureiras", by Tarsila do Amaral, from 1950, oil on canvas, measuring 73.3 × 100.2 cm from MAC-USP Museum Collection.

This study sought to develop an HPLC (high performance liquid chromatography) methodology to quantify the two main protein fractions of whey protein concentrates (WPC) in liquid and powdered form before and after microparticulation and at various protein concentrations. Additionally, we calculated the denaturation percentage of each protein fraction.

Chalcones, triterpenes, sitostenone, and very-long fatty acids were isolated from bioactive extracts of Bowdichia virgilioides’ roots.

High performance liquid chromatography-diode array detector (HPLC-DAD) and spectrophotometric methods were applied to determine bioactive phenolic compounds in Schinus terebinthifolia Raddi fruits. Antioxidant and antimicrobial activity were assessed. Metals were also determined by flame atomic absorption spectrometry (FAAS).

It was demonstrated a process improvement in the wet milling of efavirenz, increasing the concentration of solids in the suspension, and incorporating the powder into dispersible tablets.

High concentrations of ammonia in natural waters indicate pollution and environmental degradation. In this study, we propose a simple, rapid, and cost-effective voltammetric method for quantifying NH₃ in water samples using a non-modified Pt electrode.

7-Chloro-1-ethyl-6-fluoro-3-(5-oxo-4-phenyl-4,5-dihydro-1H-1,2,4-triazol-3-yl)quinolin-4(1H)-one (11e) as a potential multi-targeting agent against cholinestaeses (AChE and BChE) and monoamine oxidases (MAO-A and MAO-B) for the treatment of Alzheimer’s disease.

The pineapple peel biomass was subjected to chemical pretreatment experiments of organosolv delignification, and acid pretreatment with sulfuric acid (H₂SO₄) and hydrochloric acid (HCl), to enable the hydrolysis of hemicellulose and cellulose and obtain the fermentable sugars.

Silicone rubbers were tested as passive samplers to determine the presence of third-generation antifouling biocides, commonly used as reinforcing agents in underwater paints. The chromatographic conditions provided an efficient separation and quantification of the analytes.

Synthesis of Fe-TiO₂ from natural ilmenite and its application in the photodecomposition of aqueous cyanide (FeTiO₃).

Compound 1^•+, which is the largest reported monoradical cation of thiophene-modified pyrene, has broad application prospects in the fields of semiconductors and optoelectronic materials.

Analysis of the adsorption process of different pesticides using functionalized single-walled carbon nanotubes (SWCNT) using the AMBER/PM3 hybrid method and Monte Carlo simulation.

Expired amoxicillin and penicillin V potassium tablets form a protective film on the surface of the lowcarbon steel, reducing the direct contact between the steel and the corrosion solution, thus alleviating the corrosion of the steel.

Interpretation of physical-chemical and chemical shallow groundwater quality for human consumption, using statistical techniques.

Volatile organic compounds extracted of Protium ovatum were collected in five different vegetation physiognomies of the Brazilian Cerrado and analyzed by GC-MS (gas chromatography coupled to mass spectrometry). Posteriorly, these were tested against Staphylococcus aureus, Escherichia coli, and Candida albicans. Chemometric tools were used.

In exposed geomembrane applications, polyethylene (PE) is in contact with ultraviolet (UV) radiation, and the degradation is led by photo-oxidation with several free radical reactions.

PSI-MS spectra of urine samples from control individuals and patients with prostate cancer used in multivariate calibration with orthogonal correction to develop the OPLS-DA model.

Mole fraction of 6 and 9 determined through the intersection of the graphs obtained by solving the Schröeder-van Laar equation for the formulation of the binary mixture UR10. Background image is the nematic texture of sample UR10 by polarized optical microscopy.

HBeta, USY, and HZSM-5 zeolites produce solketal from glycerol and 2,2-DMP with higher yield under mild conditions.

In this paper, we describe the hydrothermal synthesis of Nb₂O₅ and their application in photodegradation of dyes (methylene blue (MB) and indigo carmine (IC)) and photoesterification of free fatty acids (FFA) which are present in waste cooking oil (WCO).

The synthesis of the coordination complex between aceclofenac and lanthanum or gadolinium ions results in stable compounds with potential medical and catalytic applications. Thermoanalytical characterization reveals information about the structure and thermal stability, while thermokinetic analysis investigates reaction rates, decomposition, and phase transitions, contributing to an overall understanding of the thermal behavior of the complex.

A phytochemical study from aerial parts of Pavonia glazioviana Gurke led to identify fifteen compounds, with emphasis on the polymethoxylated flavonoids that showed antimicrobial activity.

Amburana acreana Ducke leaves afforded coumarin, p-hydroxybenzoic, vanillic acids, campesterol 3-β-D-glucoside and amburoside B.

Bisphenol A (BPA) is challenging to remove in conventional wastewater treatment. In this study, with the laccase enzyme from Pleurotus ostreatus induced by acai berry and pineapple residues, BPA was effectively degraded within 4 hours.

This paper describes a synthesis, and characterization of an organofunctionalized silica (Sil-TMSDT) and its application as a solid phase in the preconcentration (SPE) of Pt⁴⁺ ions in aqueous media, using detection by flame atomic absorption spectrometry (FAAS).

This work deal with the phytochemical and dereplication studies, as well as antimicrobial and anticholinesterase evaluation of Palicourea tomentosa.

Schiff bases (SB) are diverse organic compounds, holding potential in both chemistry and biology. We explored an amino benzoic acid SB that presents a stable intramolecular hydrogen bond by cyclic voltammetric profiles supported by computational protocol to estimate redox potentials.

The application of liquid swine waste doses to a clayey Cerrado Oxisol improved its physical, chemical, and electrochemical attributes, leading to an increase in nutrient availability for plants and clay aggregation.

UiO-66-type Metal-Organic Frameworks (MOFs) were synthesized with functionalized organic linker. UiO-66-NH₂ has the highest CO₂ adsorption capacity.

A workflow for analytical procedures promoting quality control and quality assurance in untargeted metabolomics.

Dyes of natural origin are an inspiration for the development of new molecules. Several computational methods can be used to deepen knowledge of these compounds' photophysical properties, from methods based on quantum mechanics to machine learning strategies.

Layered double hydroxides are multifunctional agents as catalytic mediators in reaction processes of paramount importance.

The existence of mobile colloidal fractions favors the transport of pollutants through the soil, even when strongly sorbed.

This review provides an overview of recent advancements in organic electrosynthesis in Brazil. It highlights the principles, applications, and limitations of various electrosynthetic methodologies, aiming primarily to enhance the understanding of fundamental principles and stimulate research in this field.

Wax lipids primarily consist of aliphatic acyclic compounds, which are often misidentified by Standard Digital Libraries. WaxAlly is a new software developed to assist in identifying the mass spectra of the main classes of wax lipids.

Adsorption Kinetics Calculation (AKC) is a new free, easy-to-use software that uses non-linear equations to calculate adsorption kinetics parameters with precision, fast performance and a user-friendly interface.

The invention aims to improve the calibration of gas sensors not covered by a membrane using a system for mixing solutions with different gas concentrations.

Practical electrochemistry activities seen from an accessible microscopic perspective: water electrolysis and steel corrosion.

We show in this study that there is a strong hierarchy in the field of chemistry in Brazil. The dominant pole consists of researchers with high scientific capital and prestige. On the other side, we identified researchers with fewer resources and possibilities of raising the hierarchy.

Integrating the chemical, historical, physical, and mathematical concepts encompassed by crystallography in the determination of crystal structure through X-ray diffraction fosters a more comprehensive and effective grasp of this powerful interdisciplinary tool.

The acetylsalicylic acid produced in the experimental classes, which would typically be discarded, is recycled through purification and characterization for later use as a fingerprint developer.

Graphical summary of the theoretical aspects (one-pot synthesis) that will be explored in this work, which aims to contribute to the chemistry teaching in Brazilian higher education.

Chemistry education focused on citizenship education, ethics in interpersonal relationships and mainly criticism of social and cultural inequalities.

The construction of arguments by solving experimental problems with the help of the heuristic diagram.

How to interpret it? Perform a PCA (principal component analysis). And, how to interpret the PCA results?

The training of Chemistry teachers by higher education institution in the state of Goiás in relation to radioactivity presents gaps that reverberate in the teacher's performance in basic education.

Comparative splitting of spectroscopic terms for a p² electronic configuration following LS and jj spin-orbit coupling schemes.

The 4^th Industrial Revolution is promoting a paradigm change in the society. Chemistry alignment with the 4.0 scenario requires the involvement of chemists towards some technological challenging themes already in course.

In this article, we present a ChemTech acceleration program where the academic participants (researchers and students) develop entrepreneurial skills while taking their chemical technologies from universities to the market/industry.

Ana Rosa Kucinski Silva, lecturer in the Department of Chemistry at the University of São Paulo, was kidnapped and murdered in 1974 by the Brazilian military dictatorship (1964-1985). Very little is known about her academic activities. This work aims to contribute to fill this gap.

Escalab is a chemical technology and innovation lab at Universidade Federal de Minas Gerais (UFMG) structured to take technologies to the market and connect academy-industry focused on scale up, business modeling and startup creation.

One of the most important equations in the history of chemistry. It represents the culmination of decades of conceptual and experimental evolution in the field of electrochemical systems and still today stands as one of the pillars of modern electrochemistry.

Alfred Schaeffer (center) in one of his classes for medical and pharmaceutical courses at the Faculty of Medicine of Belo Horizonte in the 1910s.