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The staggering amount of chemicals in clothes and their harmful effects on human health and the environment have attracted the attention of regulatory agencies and the scientific community worldwide. Azo dyes are synthetic dyestuffs with widespread use in textile industries, currently classified as emerging pollutants of great health concern to consumers. These compounds may release one or more aromatic amines (AAs) after reductive cleavage of their azo bounds. Twenty-two AAs have already been regulated due to their carcinogenic effects. However, since information on their potential toxicity is not currently available, several AAs have not been still regulated by the European Union. Considering this gap, the present study aimed to assess the levels of forty non-regulated AAs in 240 clothing items from Spain and Brazil. The potential impact on the health of vulnerable population groups after dermal exposure to those garments was also evaluated. In Brazil, at least one AA was detected in the clothes, while in samples obtained in Spain, only two of them showed values below the limit of detection for AAs. In 75 clothes, at least one of the measured AAs was higher than the hazardous threshold (30 mg/kg), which can mean risks to human health since these compounds are suspected to be mutagenic. Aniline, the most common AA, showed a high detection rate (82%) in clothes, with significantly higher concentrations in items commercialized in Brazil (0.35 vs. 0.17 mg/kg; p = 0.032). Moreover, o-aminobenzenesulfonic and p-phenylenediamine, suspected mutagenic, were found at relevant concentrations in several clothes, mainly made of synthetic fibers. In this study, the hazard index associated with exposure to AAs through clothing was low (0.006-0.13) for all the population groups of both countries in the medium-bound scenario. However, its value was close to 1 for Brazilian pregnant women (0.998) when the maximum concentration value was considered under an upper-bound scenario. The risk of exposure to non-regulated AAs may be underestimated since only dermal exposure was considered for risk assessment. Moreover, the co-occurrence of other carcinogenic and non-carcinogenic substances present in skin-contact clothes should mean an additional source of potential risk.

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This paper describes a fast, sensitive, environment-friendly method for the determination of 19 primary aromatic amines (PAAs) in cooking utensils by capillary zone electrophoresis coupled with tandem mass spectrometry. The best electrophoretic separation of PAAs was obtained in 0.1 mol l-1 formic acid (pH 2.4) as the background electrolyte, fused silica capillary (67 cm) with a run time below 6 min. The proposed method presented a linear calibration with correlation coefficients higher than 0.99 and reproducibility in a range of 1-25%. Limits of detection were in the range of 0.2-1.3 µg kg-1 and recoveries were in a range of 85-120% for all the PAAs. The validated method was employed to determine PAAs on 36 samples of cooking utensils using acetic simulant. The results showed that 4,4'-diaminodiphenylmethane and aniline being the most frequently found PAAs in these samples and 28% of cooking utensils were not compliant.

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BACKGROUND: Several compounds have been synthesized as a therapeutic alternative for heart failure; however, its preparation requires special conditions. OBJECTIVE: The aim of this study, was to synthesize some aniline derivatives (4-9) from 3- ethynylaniline to evaluate their biological activity against heart failure. METHODS: The synthesis of aniline derivatives involved a series of reactions such as etherification, addition, and cyclization. The structure of all compounds obtained was confirmed by spectroscopic and spectrometric methods. In addition, to evaluate the biological activity of compounds, an ischemia/reperfusion injury model was used. RESULTS: The results showed that compound 8 decreases heart failure, which translates into a decrease in the infarction area compared to compounds 4-7 and 9. CONCLUSION: This study reports a facile method for the preparation of aniline derivatives. This method offers some advantages such as; a simple procedure, low cost, and easy work up. In addition, compound 8 showed an interesting biological activity against heart failure. This phenomenon is particularly interesting because the biological activity induced by this compound could involve a molecular mechanism that is different from other drugs used for the treatment of heart failure.

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Herein, a greener approach to the eosin Y-Na2 catalyzed, C(sp2 )-H bond azo coupling of imidazoheteroarene with aryl diazonium salts is described, under acid free conditions. This direct photoredox process resulted in the corresponding azo products in good to excellent yields. Besides, this new approach could also be applicable to anilines, which is a poorly reactive substrate by other methods. The main features of this reaction are that it provides high yields and is gram-scalable and applicable to biologically relevant imidazoheteroarenes and -anilines.

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The purpose of this research is to demonstrate through a techno-economic assessment that aniline can be industrially produced using a profitable and inherently safer process than the ones currently employed. The aniline production process was designed using process simulation software. From this, the mass and energy balances were determined, the equipment sizing was performed and the net present value (NPV) was calculated to be USD 93.5 million. Additionally, a heat integration analysis was carried out in order to improve process profitability, obtaining a new NPV of USD 97.5 million. The economic sensitivity analysis showed that the process could withstand fixed capital investment changes of up to +89%, weighted average cost of capital changes between 16-24% and a decrease in cyclohexylamine demand of up to 44%. The conceptual design is still profitable when aniline price is varied in a range of 1224-1840 $/t and phenol cost in a range of 815-1178 $/t.

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A oxidação eletrocatalítica de paracetamol, acompanhada ou não pela eletropolimerização do próprio, sobre poli(azul da anilina) foi descrita matematicamente (usando a teoria de estabilidade linear e análise de bifurcações). Para o comportamento do composto foi sugerido o mecanismo que concorda com os dados experimentais e com os cálculos teóricos. Foi investigada também a dependência do desempenho do polímero e do comportamento do composto do pH.

The electrocatalytic paracetamol oxidation over poly(aniline blue), accompanied or not by its electropolymerization, has been described mathematically (using the linear stability theory and bifurcation analysis). For the compound' s behavior a mechanism, according with the experimental data and theoretical calculations, has been suggested. Also the pH-dependence of the work of the polymer and the compound' s behavior has been investigated.

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Herein we show the synthesis and characterization of water dispersible composites formed by poly(aniline) and the natural polymer gum Arabic (GA), used as stabilizer. The materials were synthesized via a rapid and straightforward method and were fully characterized by different techniques such as UV-Vis, Raman, FTIR, TEM, SEM and cyclic voltammetry. TEM and SEM images revealed that the proportion of stabilizer highly influences the growth mechanism of the nanostructures. It was found spherical particles, elongated structures and large agglomerates at the lower, intermediate and at the higher GA amount, respectively. Accordingly to fluorescence spectra, different hydrophobic structures are formed depending on the GA amount in aqueous solutions, possibly acting as hosting sites for the PANI growth. In order to further study the PANI polymerization in the presence of GA, kinetics experiments were performed and showed that nucleation is the limiting step for the composite growth and a model is proposed. Spectroscopic experiments showed that the presence of GA affects the PANI conformation, avoiding the formation of phenazine structures which highly impairs the electroactivity of PANI. The material integrity is achieved by strong hydrogen bond interactions between PANI and GA as evidenced by the study of specific NH bands in FTIR and Raman analyses. The intensity of the hydrogen bonds decreased upon higher amounts of GA, probably due to steric impediment around the NH sites. Cyclic voltammograms showed a good electroactivity behavior of the modified electrodes presenting distinguishable diffusional processes through the adsorbed composites. By this way, we have thoroughly investigated the formation and properties of new conducting polymer composite materials. Taken into account the low toxicity of GA and the excellent dispersity in water, the materials can successfully be applied in bioelectrochemical applications or as green corrosion inhibitors.

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In the title compound, C13H10BrNO2, the mean plane of the non-H atoms of the central amide C-N-C(=O)-C fragment (r.m.s. deviation = 0.004 Å) forms a dihedral angle of 73.97 (12)° with the hy-droxy-substituted benzene ring and 25.42 (19)° with the bromo-substituted benzene ring. The two aromatic rings are inclined to one another by 80.7 (2)°. In the crystal, mol-ecules are linked by O-H⋯O and N-H⋯O hydrogen bonds, forming chains along [010]. The chains are linked by weak C-H⋯O hydrogen bonds, forming sheets parallel to (100), and enclosing R (3) 3(17) and R (3) 2(9) ring motifs.