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An environmentally friendly methodology for the synthesis of different functionalized sulfones is described here.

Resumo A injustiça epistêmica agencial no processo penal ocorre quando se imputa excessiva credibilidade a declarações prestadas pelo locutor em momentos de reduzida capacidade de autodeterminação. Especificamente no contexto da retratação de confissões extrajudiciais, questiona-se quais critérios jurídicos de valoração probatória racional seriam capazes de prevenir a ocorrência de injustiças agenciais. A metodologia empregada foi a pesquisa bibliográfica em injustiça epistêmica, confiabilidade probatória da confissão e precedentes do Superior Tribunal de Justiça. Analisando estudos empíricos sobre falsas confissões e as práticas forenses brasileiras, constata-se um risco relevante de ocorrência dessa forma de injustiça, tendo em vista que confissões extrajudiciais são largamente utilizadas para fundamentar sentenças condenatórias. O artigo conclui com duas propostas: (I) desconsiderar, para fins de valoração da prova, confissões extrajudiciais não confirmadas em juízo; e (II) adotar como um dos critérios de valoração da confissão o grau de efetiva agência epistêmica do acusado ao confessar, atribuindo-se menor credibilidade às confissões obtidas em situações de agência reduzida. Abstract Agential epistemic injustice in criminal prosecution occurs when declarations taken in moments of reduced capacity for self-determination receive excessive credibility. Specifically in the context of recanted out-of-court confessions, the article investigates which legal criteria for the rational evaluation of evidence could prevent agential injustices. The method employed was bibliographical research on epistemic injustice, reliability of confessions as criminal evidence, and the Superior Court of Justice’s case law. Analyzing empiric research on false confessions and forensic practices in Brazil, a significant risk for agential injustices can be detected, mainly because out-of-court confessions are largely used to justify criminal convictions. The article concludes with two propositions: (I) to disregard, during the evaluation of evidence, out-of-court confessions not repeated before a judge; and (II) to consider the level of the defendant’s effective epistemic agency when evaluating their confession, with less credibility given to confessions obtained in situations of reduced agency.

Pretende o presente trabalho analisar as atividades de investigação defensiva, abordando a partir dos precursores do tema até a materialidade de disposições normativas a respeito, trazendo seus contornos doutrinários e práticos. Além do mais, almeja o presente trabalho analisar e destacar a importância do assunto, principalmente seus aspectos contributivos para melhor instrução do processo acusatório, desde sua fase preliminar até sua aplicação na última fase da persecução penal. Inclusive, o resultado da pesquisa sobre a matéria objeto do presente trabalho científico revelará a importância da aplicação da investigação defensiva em prol de uma persecução penal que seja a mais justa possível.

The study aimed to identify interspecies interactions within a native microbial community present in a hydrogen-producing bioreactor fed with two wheat straw cultivars. The relationships between the microbial community members were studied building a canonical correspondence analysis and corroborated through in vitro assays. The results showed that the bioreactor reached a stable hydrogen production of ca. 86 mL/kg·d in which the cultivar change did not affect the average performance. Lactobacillus and Clostridium dominated throughout the whole operation period where butyric acid was the main metabolite. A canonical correspondence analysis correlated positively Lactobacillus with hydrogen productivity and hydrogen-producing bacteria like Clostridium and Ruminococaceae. Agar diffusion testing of isolated strains confirmed that Lactobacillus inhibited the growth of Enterococcus, but not of Clostridium. We suggest that the positive interaction between Lactobacillus and Clostridium is generated by a division of labor for degrading the lignocellulosic substrate in which Lactobacillus produces lactic acid from the sugar fermentation while Clostridium quickly uses this lactic acid to produce hydrogen and butyric acid. The significance of this work lies in the fact that different methodological approaches confirm a positive association in the duo Lactobacillus–Clostridium in a bioreactor with stable hydrogen production from a complex substrate. HIGHLIGHTS Native microbiota of wheat straw reached a stable hydrogen production.; Microbial structure was stable dominated by Lactobacillus and Clostridium.; Statistical analysis and in vitro assays demonstrated positive interactions.; Division of labor in lignocellulose consumption could promote positive interactions.

The relationship between the taxonomic diversity and the function of microbial communities is complex. Specifically, the ecological mechanisms that drive the dynamics of microbial populations and the consequences of these dynamics on functional traits have remained elusive. Among the simplest but natural microbial communities are dark fermentation consortia, a subset of the more diverse and complex microbial communities, anaerobic digestion communities. Dark fermentation consortia have been of interest as they produce biofuels such as hydrogen and different alcohols that can be used as fossil fuels alternatives. However, these hydrogen-producing communities have unresolved instability and low yield issues. We have previously proposed that instability and low yields in dark fermentation communities could be due to reduced diversity that results from aggressive pretreatments of original anaerobic digestion communities. In this work, we used dark fermentation communities to examine experimentally the effect of diversity reduction in functional traits, including stability and microbial interactions. We established two types of treatment, (i) maintaining strict culture conditions that are known to induce hydrogen production and ii) applying a heat-shock treatment known for selecting hydrogen-producing bacteria, which resulted in two types of communities, high and low diversity. Each treatment consisted of 12 replicates that were transferred to fresh medium daily (during 28 days for the non-treated bioreactors and 61 days for the heat-shock treated bioreactors). Microbial communities of the two treatments were characterized in their function as well as resistance to invasion. Microbial composition was characterized by culture-independent 16S rRNA gene amplicon sequencing. We analyzed microbial community composition and function through time, establishing statistical relationships between bacterial groups and metabolite production. Also, we inferred the potential ecological interactions that might have been established. Results show that the replicate bioreactors for each treatment predictably shifted to a similar composition and increased and stable biogas production. The non-treated bioreactors showed less susceptibility to the invasion (with the invasive bacteria establishing only in one replicate in the non-treated bioreactors vs 6 invaded replicates of the heat-shock treated bioreactors). However, the effect observed in the non-treated bioreactor replicate where the invader bacteria established was more drastic since the invasive bacteria managed to become dominant.

Research in dark fermentation has emphasized an engineering view of bioreactors overlooking its integration with the ecological dynamics of the process. Ecological dynamics driven by microbial interactions impact bioreactors performance and are critical to understanding the mechanistic bases of dark fermentation. We propose an analytical framework consisting of “description”, “association” and “modeling” phases or inquiry levels to elucidate potential ecological interactions in bioreactor-associated microbial consortia. Each phase deepens into obtaining mechanistic insights of the microbial behavior in bioreactors. We present a study case to illustrate each step of the framework, their limitations and opportunities. We show that analytical frameworks integrating metabolic data and microbial diversity give insights into the ecological processes underlying the performance of dark fermentation bioreactors and can guide future research through informed hypotheses.

Benzylic alcohols have an important role in organic synthesis as target molecules of biological interest, which can be produced from the reduction of aromatic carbonyl substrates. In this work, the sonoelectrocatalytic hydrogenation (SECH) of aryl ketones was studied in water. The ultrasonic irradiation was carried out at frequency of 20 kHz ±500 Hz with a cylindrical titanium probe (MS 73 microtip; Ti-6AI-4V alloy; 3.0 mm diameter; Pacoustic = 2.11 W). The results showed that the ultrasound irradiation enhances the mass-transport of the substrates from the bulk solution to the electrode surface, increasing the substrate availability to react with the adsorbed H, leading to higher yields. Regarding the electrode material, the following hydrogenation yields of a group of acetophenones was observed: Cu (79.0 ± 1.5%) > Ni (73.0 ± 2.0%) ≈ Fe/Ni (72.0 ± 1.7%) > graphite (69.0 ± 1.7%) > Fe (67.5 ± 2.3%). The SECH presented a slight variation in the reactivity of some reagents, and its behaviour depends on the catalytic nature of the electrode support. Besides the lower overpotential and higher exchange current density of the graphite, it was surprisingly active under ultrasound irradiation, showing higher yields and current efficiencies than others electrocatalytic hydrogenation (ECH) procedures. The ultrasound irradiation decreases more than 6-folds the energy consumption of the ECH method, making it an effective and inexpensive way to produce alcohols from the respective aryl ketones in water.

In this work, the boron-doped diamond electrode (BDDE) was used for the electrocatalytic oxidation of N-acetylcysteine (NAC), in the presence of lipoic acid (LipS2), which works as an organic homogenous electrochemical catalyst. Cyclic voltammetry (CV), controlled-potential electrolysis, and differential pulse voltammetry (DPV) were performed in buffered aqueous solution at pH 7.0, in order to study the proposed system. Several analytical figures of merit were obtained for NAC, including a linear response range from 1 up to 100 μmol L−1 and detection limit of 93 nmol L−1. The method was successfully applied to the quantification of NAC in pharmaceutical preparations (capsules, syrup, and suspension), without matrix effects. The present study shows that the redox reaction between the studied thiolate and the electrogenerated cation radical of LipS2, regenerating the original compound, on BDDE, is a promising analytical tool for quantifying NAC, in a relatively low oxidation potential, very simple, rapid, convenient, sensitive, and low-cost way.

The electrochemical generation of sulfinyl radicals from commercially available and non-expensive sodium salts of sulfinic acids is described. Electrooxidation reactions were carried out in a graphite powder macroelectrode using an aqueous electrolyte and cavity cell. Further reaction with primary or secondary amines gave the corresponding sulfonamides, a unit present in several biologically active compounds and pharmaceuticals, in good yields.

The eco-friendly aqueous electrosynthesis of AgIn5Se8 (AISe) nanocrystals (NCs), and their respective core/shell structure AgIn5Se8/ZnS NCs (AISe/ZnS), was carried out by using L-glutathione (GSH) as a stabilizer. Se0 direct reduction was carried out in a graphite powder macroelectrode of an electrochemical cavity cell, controlled by current (i = 30 mA) and electric charge (Q = 11.6 C). The generated Se2− ions react with In3+ and Ag+ ions in the intermediate compartment of the cell to give AISe NCs. A paired electrolysis (Zn0 anode/S0 in a graphite powder cathode) was carried out to prepare ZnS-GSH NCs, using the same electrochemical apparatus (i = 30 mA and Q = 9.6 C). The effects of the Ag+/In3+ ratio (0.5, 0.28 and 0.18) and ZnS shell on the optical properties of AISe NCs were investigated. The ternary AISe NCs were characterized by XRD and HRTEM, which revealed that AgIn5Se8 had a cubic phase structure (Ag+/In3+ = 0.18) and the ZnS shell had a zinc blende structure. The shell growth promoted a heterojunction formation with different crystalline phases, leading to a quantum yield decrease (QY: AISe = 18.6%; AISe/ZnS = 16.0%). The NCs were irradiated with a near-infrared laser at different power densities (λexc = 785 nm). AISe and AISe/ZnS samples showed photothermal response, reaching 381 K and 402 K, respectively.

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Human lifestyle and its relationship with the human microbiome has been a line of research widely studied. This is because, throughout human history, civilizations have experienced different environments and lifestyles that could have promoted changes in the human microbiome. The comparison between industrialized and non-industrialized human populations in several studies has allowed to observe variation in the microbiome structure due to the population lifestyle. Nevertheless, the lifestyle of human populations is a gradient where several subcategories can be described. Yet, it is not known how these different lifestyles of human populations affect the microbiome structure on a large scale. Therefore, the main goal of this work was the collection and comparison of 16S data from the gut microbiome of populations that have different lifestyles around the world. With the data obtained from 14 studies, it was possible to compare the gut microbiome of 568 individuals that represent populations of hunter-gatherers, agricultural, agropastoral, pastoral, and urban populations. Results showed that industrialized populations present less diversity than those from non-industrialized populations, as has been described before. However, by separating traditional populations into different categories, we were able to observe patterns that cannot be appreciated by encompassing the different traditional lifestyles in a single category. In this sense, we could confirm that different lifestyles exhibit distinct alpha and beta diversity. In particular, the gut microbiome of pastoral and agropastoral populations seems to be more similar to those of urban populations according to beta diversity analysis. Beyond that, beta diversity analyses revealed that bacterial composition reflects the different lifestyles, representing a transition from hunters-gatherers to industrialized populations. Also, we found that certain groups such as Bacteoidaceae, Lanchospiraceae, and Rickenellaceae have been favored in the transition to modern societies, being differentially abundant in urban populations. Thus, we could hypothesize that due to adaptive/ecological processes; multifunctional bacterial groups (e.g., Bacteroidaceae) could be replacing some functions lost in the transition to modern lifestyle.

O presente artigo propõe a compreensão do que são grupos de pressão e como esses grupos agem ao influenciar o processo legislativo no Brasil e no mundo, explorando, ainda, o recorte social e jurídico da efetividade de sua ação, no que concerne à legislação criminal vigente no país. Nesse sentido, é indispensável esclarecer que o Direito Penal se orienta, quando da produção legislativa, em conformidade com uma (pre)suposta racionalidade relacionada, ex ante, a interesses setoriais. This article proposes an understanding of what pressure groups are and how these groups act to influence the legislative process in Brazil and in the world, also exploring the social and legal framework of the effectiveness of their action, with regard to the criminal legislation in force in the country. In this sense, it is essential to clarify that the Criminal Law is oriented, when producing legislation, in accordance with a (supposed) rationality related, ex ante, to sectorial interests.

Here, we report the preparation and characterization of stable AgIn5Te8 (AITe) nanocrystals (NCs) and their respective AITe–ZnS and AITe–ZnSe alloys. A green route of synthesis is described by using an aqueous electrochemical method in a cavity cell. The elemental ratio modulation of the NCs was investigated to determine the ideal improvement of the structural and electronic properties. The AITe NCs presented an emission band at 889 nm and hypsochromic shifts when coated with ZnS and ZnSe seeds. Photothermal analyses point to theranostic applications.

The heat-shock pretreatment (HST) is a useful method to select for H 2 -producing inocula when soluble substrates are employed. However, the HST has proven to have negative effects on the H 2 production performance from lignocellulosic substrates. We hypothesize that the negative effect of HST on H 2 production from lignocellulosic substrates is due to the loss of species involved in cellulose solubilization. In the present study, we tested this hypothesis by applying a heat-shock pretreatment (105 °C/24 h) on the microbial community for producing hydrogen from microcrystalline cellulose. Specifically, we compared a microbial community treated with 2-bromoethanesulfonate (BES-treated control) versus a heat-shock pretreated microbial community. For both experimental treatments, we determined the major fermentation products (hydrogen, acetic, butyric, propionic, and isovaleric acids), as well as the diversity of bacteria and fungi using Illumina MiSeq of amplicons in five sampling points. We found that HST immediately reduced alpha diversity of microbial communities, being fungi more affected than bacteria. We also found that the bacterial reduction in Comamonas , Ureibacillus , and Aneurinibacillus was related to a low hydrogen production in the heat-shock pretreated community. Strictly anaerobic fungi such as Orpinomyces , Cyllamyces , and Neocallimastix , which are recognized by their role in solubilization of fibrous materials, were unable to survive the HST. The reconstructed bacterial network predicted positive interactions between cellulase-producing and hydrogen-producing families. We conclude that the HST did not promote the high microbial diversity required for hydrogen production from cellulose.

The rhizosphere provides several benefits to the plant host being a strong determinant for its health, growth and productivity. Nonetheless, the factors behind the assembly of the microbial communities associated with the rhizosphere such as the role of plant genotypes are not completely understood. In this study, we tested the role that intraspecific genetic variation has in rhizospheric microbial community assemblages, using genetically distinct wild cotton populations as a model of study. We followed a common garden experiment including five wild cotton populations, controlling for plant genotypes, environmental conditions and soil microbial community inoculum, to test for microbial differences associated with genetic variation of the plant hosts. Microbial communities of the treatments were characterized by culture-independent 16S rRNA gene amplicon sequencing with Illumina MiSeq platform. We analyzed microbial community diversity (alpha and beta), and diversity structure of such communities, determined by co-occurrence networks. Results show that different plant genotypes select for different and specific microbial communities from a common inoculum. Although we found common amplicon sequence variants (ASVs) to all plant populations (235), we also found unique ASVs for different populations that could be related to potential functional role of such ASVs in the rhizosphere.

Made available in DSpace on 2020-12-10T17:39:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-08-04 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) FINEP FAPEAL (Alagoas State Research Agency) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Environmental conditions have a profound effect on the photophysical behavior of highly conjugated compounds, which can be exploited in a large variety of applications. In this context, we use a combination of experimental and computational methods to investigate thermal and solvatochromic effects on the fluorescence properties of a dansyl derivative bearing a thienyl substituent, namely 2-(3-thienyl)ethyl dansylglycinate (TEDG). In particular, we analyze how the solvent polarity and temperature affect the ground and excited state energies of TEDG by using time-resolved and steady-state fluorescence techniques. We determine the changes in dipole moment of the TEDG molecule upon photoexcitation, as well as the solvent polarity effects on the excited state lifetime. Besides, we provide theoretical modeling of the HOMO-LUMO orbitals and the vertical absorption and emission energies using time-dependent density functional theory (TDDFT) as well as the polarizable continuum model (PCM) to include the solvent contribution to the absorption and emission energies. Our results show that the emission mechanism of TEDG involves locally excited states derived from hybrid molecular orbitals, accompanied by a moderate variation of the molecular dipole moment upon light excitation. Our findings demonstrate that TEDG exhibits desirable fluorescence properties that make it a promising candidate for use as a photoactive material in electrochromic, optical thermometry, and thermography applications. Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Fis, BR-14040901 Ribeirao Preto, SP, Brazil Univ Estadual Paulista, Fac Ciencias & Tecnol, Dept Fis, BR-19060900 Presidente Prudente, SP, Brazil Univ Fed Alagoas, Inst Quim & Biotecnol, BR-57072970 Maceio, Alagoas, Brazil Univ Fed Alagoas, Inst Fis, BR-57072970 Maceio, Alagoas, Brazil Univ Fed Pernambuco, Dept Quim Fundamental, CCEN, BR-50670901 Recife, PE, Brazil Inst Fed Piaui, Campus Angical, BR-64410000 Angical, PI, Brazil Univ Estadual Paulista, Fac Ciencias & Tecnol, Dept Fis, BR-19060900 Presidente Prudente, SP, Brazil CNPq: 438198/2018-2 CNPq: 305771/2016-7

This article is part of the comparative studies on organization and curriculum development, in the area of ​​Mathematical Education, in Brazil, Chile and Mexico. The intention is to highlight the impacts of the research results in Mathematics Education in the official documents of these countries, elaborated from the 90s of the 20th century and present similarities and differences of the Prescribed Mathematics Curricula. It was used as a path from the curricular comparison to the Comparative Education of documents that prescribe the educational systems and the Mathematics Curricula of basic education. The comparative analysis points out a differentiation in the curricular structure, an emphasis on algebra in the Chilean and Mexican curriculum and similarity as the use of problem solving in the teaching and learning process in the three countries. Este artigo insere-se no contexto dos estudos comparativos sobre organização e desenvolvimento curricular, na área de Educação Matemática, no Brasil, Chile e México. A intenção é evidenciar os impactos dos resultados de pesquisa em Educação Matemática nos documentos oficiais desses países, elaborados a partir dos anos 90 do século XX e apresentar semelhanças e diferenças dos Currículos Prescritos de Matemática. Utilizou-se como percurso da comparação curricular a Educação Comparada de documentos que prescrevem os sistemas educacionais e os Currículos de Matemática da educação básica. Na análise comparativa aponta-se uma diferenciação na estruturação curricular, ênfase da álgebra no currículo chileno e mexicano e semelhança como o uso da resolução de problema no processo de ensino e aprendizagem nos três países.

A new greener strategy to incorporate Bi2S3-mercaptopropionic acid (MPA) quantum dots (QDs) onto TiO2 nanotube (NT) films was developed, using in situ electrochemical synthesis with a graphite/sulfur powder macroelectrode (cathode) and cavity cell. Simultaneously, the obtained QDs were adsorbed on TiO2 NTs, for the photoelectrochemical cell (PEC) assays. After the electrochemical synthesis, different thermal post-treatments were performed for growth and crystallization of obtained nanocrystals. The obtained TiO2–Bi2S3 nanostructured composites were characterized by UV–vis, diffuse reflectance spectroscopy, X-ray diffraction, scanning electron microscopy and transmission electron microscopy. Photoelectrochemical tests were carried out, where TiO2 NTs/Bi2S3 QDs with 15 min post-treatment at 90 °C presented a greater photocurrent density, when irradiated with visible light (427–655 nm region, 10 mW.cm–2) and compared to pristine TiO2 NTs. Such performance can be attributed to the synergetic effect caused by ...

This work proposes a fluorescent probe based on CdTe quantum dots (QDs) for the determination of resveratrol in wine samples. The synthesis of cysteamine (CA) capped CdTe QD was carried out in a one-pot eco-friendly process, resorting to the electrochemical reduction of metallic tellurium powder in a graphite macroelectrode (cavity cell). The reduced species of tellurium (Te2− and Te22−) migrated to an intermediate compartment of the electrochemical cell and in the presence of a cadmium salt and organic stabilizing agent (CA), forming the colloidal dispersion of CdTe in a single step. Under optimum synthesis conditions, the fluorescence intensity of the prepared nanoparticles varied linearly with the resveratrol concentration in the range from 3.25 to 75 μg L−1 (R2 = 0.9984), with a detection limit of 0.97 μg L−1 and RSD of 3.7% (5.0 μg L−1 resveratrol, n = 10). The method was successfully applied to the resveratrol determination in wines, with recoveries from 97.8 to 112.4%. Student’s t test was applied and no statistically significant difference was observed between the two methods (HPLC and proposed), with a confidence level of 95% (ttabulated = 2.45 and tcalculated = 0.38). The resveratrol determination method, by using CdTe-CA QDs as fluorescence probe, was simple, rapid, inexpensive, and sensitive.

The use of commercial graphite powders (different sources and particle sizes), as electrode materials, was evaluated in an electrochemical cavity cell. The graphite powders were characterized by electron microscopy, XRD, vibrational spectroscopy, porosimetry, contact angle, Boehm titration and cyclic voltammetry. Despite similarities, the graphite powders differed significantly in terms of surface functional groups (SFGs), hydrophobicity and particle size. The surface chemistry of both graphites was modified by HCl treatment, followed by 200 °C heating, prior to electrode fabrication, which was found to play an important role on the electrode performance. Cyclic voltammetries were carried out for the two different graphites in acid medium and absence of reagent, and the results were correlated to Boehm titration, showing evidences of the presence of acidic and basic SFGs. After HCl + heat treatment, it was observed the diminishing of the SFGs for both commercial graphite powders tested. The electro-reduction of benzyl bromide was used as standard reaction, yielding 1,2-diphenylethane and toluene as products. A 23 factorial design was used to optimize some electrode parameters. The compaction of the graphite electrodes showed to be fundamental for obtaining good results. HCl + heat treatment favored the 1-electron process, giving 1,2‑diphenylethane as major product on both electrodes (GF, 61% and GA, 52%). The absence of graphite powder treatment favored the 2-electron process, furnishing toluene as major product (GF, 55% and GA, 43%).

The optimum conditions for the electrocatalytic hydrogenation of (R)-(+)-pulegone in water, using ultrasound (continuous or pulsed mode) and a nickel sacrificial anode have been determined. The continuous ultrasound (14 W), without temperature control, showed to be a most effective technique if compared with pulses of 0.2 s applied after each second. The sonication of the reaction solution presented a slight stereochemical effect on the product distribution, and its magnitude depends on both the ultrasound power and the mode. Simultaneous ultrasound irradiation during electrochemical process showed a synergetic effect, able to generate H radical from water H O bond rupture, in addition to the H radicals formed by the electrochemical reduction of water on the electrode surface, increasing both current efficiency and conversion yields. Chitosan microspheres were use in the removal of nickel ions of the aqueous medium showing an adsorption efficiency of 64%.

Spent lead-acid batteries are environment emerging contaminants and very harmful to health. In this work, we developed one-pot electrochemical method of recycling lead electrodes for the preparation of Pb metal–organic framework, using 1,3,5-benzenetricarboxylic acid as organic ligand (Pb(btc)-1). In H2S solution, a color change can be observed on the Pb(btc)-1 surface, which is caused by PbS formation and, therefore, it was studied as a smart compound for H2S quantification. Colorimetric techniques, as diffuse reflectance and digital image (DI) analysis obtained on a smartphone, were used for H2S quantification. The grayscale and RGB color histograms were obtained from the recorded images and treated by partial least squares (PLS) regression method directly on a smartphone, or using the MATLAB® software. The colorimetric techniques showed greater sensitivity, resulting in a limit of detection of 0.11 mmol.L-1, which is slightly lower than the DI using MATLAB® software (0.21 mmol.L-1). The accuracies of the colorimetric techniques were similar and present feasible values when compared to Horwitz criteria. Thus, the H2S sensor ends the lead-acid battery recycling cycle, giving a colorimetric device by a low energy processing of the lead electrode.

A novel versatile and clean colloidal processing route was developed for synthesizing CdX (X = Te, Se or S) quantum dots (QDs) based on the simultaneous production of the respective precursors via cadmium sacrificial anode electrochemical methodology. The CdX QDs stabilized by 3-mercaptopropionic acid (MPA) were synthesized in one-pot electrochemical process using aqueous medium at room temperature with full reaction time of approximately 16 min. The CdX quantum dots conjugates were extensively characterized by UV–vis, PL, FTIR, TEM-EDS, XRD, DLS, XPS, and Zeta potential, evidencing that very stable colloidal quantum dots were produced with uniform narrow-size distributions and average nanoparticle diameter of approximately 3.0 nm and quantum yield (QY) of approximately 10%. The cell viability response of HeLa cells toward the CdX-MPA conjugates clearly demonstrated that they are non-toxic based on the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) mitochondrial metabolic activity assay for 24 h of incubation with HeLa cervical cancer cells. Moreover, they showed effective fluorescent activity with time-dependent intensities for evaluating continuous endocytosis of cancer cells, thus, offering innumerous possibilities to be used as fluorescent nanoprobes for bioimaging and biosensing of cancer cells.