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Natural gas has shown an increase in demand in recent years, largely due to its competitive advantages over other fossil fuels. However, in Brazil, its production and supply chain remain under the monopoly of Petrobras, which makes it difficult for new agents to enter the market and often causes other producers to dispose of their production without any financial return. Therefore, the objective of this work is to identify alternative technologies for natural gas processing, to allow other natural gas producing companies to commercialize their natural gas production without depending on Petrobras' infrastructure. As a result, three technologies were identified that are already being applied in other countries, which are: compressed natural gas, liquefied natural gas and gas-to-liquids.

Polyurethanes (PUs) have been widely used in several trade sections. Thereby, large amounts of waste are produced and need to be correctly disposed of. Research on this theme has been helping industries to apply recycling processes that are cheap and efficient. In this work, the glycolysis of a rigid PU was performed using different catalysts. 1H NMR analysis was used to obtain the rate of PU depolymerization. Glycerol (GCL) and diethylene glycol (DEG) were tested as glycolysis agents. The PU was synthesized to be free of additives in the depolymerization process, and its characterization was performed using FTIR and 1H NMR analyses. The use of NaOH as a catalyst showed a better conversion rate, as is already known in the literature. Ionic liquids (LIs) also presented good results, which can be improved by modifying the reaction conditions. To determine the composition of the mixture of products in the depolymerization reaction, diffusion ordered spectroscopy 1H NMR (DOSY-NMR) was used. DOSY-NMR indicated a complex mixture of reaction by-products, differently from the 1H NMR data, which indicated the formation of a simple diamine-terminated by-product. DOI: http://dx.doi.org/10.17807/orbital.v11i1.1385

The identification of cannabinoids directly in seeds is very controversial. According to the Recommended Methods for the Identification and Analysis of Cannabis and Cannabis products, “the seeds themselves do not contain Δ9-THC”. It is defended the idea that the detection of Δ9-THC when it possibly occurs by contact of the seed with its bracts and/or flowers of the plant, which has a high content of this cannabinoid. In this paper, we reported a simple method of extraction and fast detection of Δ9-THC in the internal part of Cannabis seeds by negative-ion mode electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI(-)FT-ICR MS). Results showed that the method proposed allowed the chemotaxonomic forensic examination to prove the identification of Δ9-THC in Cannabis seeds. DOI: http://dx.doi.org/10.17807/orbital.v10i5.1149

The objective of this study was to analyze the pedagogical aspects of teaching chemistry in a “Quixaba” school project developed with students of Science of last year of basic school (corresponding to the third cycle), focusing CTSA. The project dealt with the articulation of socio-scientific issues with content of Chemistry, focusing on some industry sectors of Espírito Santo State, such as food, construction and steel. This is a case study, qualitative, based on direct observations, technical visits and focus group interviews. The results led us to conclude that the teaching practices carried out during the “Quixaba” project provided scientific literacy focusing CTSA. DOI: http://dx.doi.org/10.17807/orbital.v7i1.681

Background: The World Health Organization declared the end of the COVID-19 pandemic in May 2023, three years after the adoption of global emergency measures. Monitoring of SARS-CoV-2 in sewage underscores its importance due to its effectiveness and cost-effectiveness, highlighting the need to prioritize research on water resources and sanitation. Objectives: The aim of this study was to conduct an epidemiological assessment of SARS-CoV-2 in the sewage system of a higher education institution located in Vitória Espírito Santo State, Maruípe campus. Methods: Over a period of 66 days, from February 6 to April 12, 2023, 15 samples were collected. Each sample consisted of 1 L, collected in 1 hour, with 250 mL collected every 15 minutes. The samples were characterized by assessing their appearance, and pH was measured using a Horiba U-50 multiparameter probe. The extracted RNA was subjected to RT-qPCR using the Allplex™ 2019-nCovAssay Seegene kit. Results: The samples exhibited a cloudy appearance with impurities, and the pH ranged from 6.35 to 8.17. Among the evaluated samples, SARS-CoV-2 RNA was detected in two, and, by comparing this with the epidemiological bulletin issued by the State Health Department, an increase in cases in the state was observed during the collection period of these samples. Conclusions: Sewage monitoring proved to be an important tool in this post-pandemic period, serving as an alert and prevention mechanism for the population in relation to new outbreaks. Furthermore, it represents a low-cost mapping strategy and extensive testing of a population, aligning with the studies presented at the beginning of the pandemic. We recommend specific adjustments considering distinct populations.

Big data launches a modern way of producing science and research around the world. Due to an explosion of data available in scientific databases, combined with recent advances in information technology, the researcher has at his disposal new methods and technologies that facilitate scientific development. Considering the challenges of producing science in a dynamic and complex scenario, the main objective of this article is to present a method aligned with tools recently developed to support scientific production, based on steps and technologies that will help researchers to materialize their objectives efficiently and effectively. Applying this method, the researcher can apply science mapping and bibliometric techniques with agility, taking advantage of an easy-to-use solution with cloud computing capabilities. From the application of the “Scientific Mapping Process”, the researcher will be able to generate strategic information for a result-oriented scientific production, assertively going through the main steps of research and boosting scientific discovery in the most diverse fields of investigation. • The Scientific Mapping Process provides a method and a system to boost scientific development. • It automates Science Mapping and bibliometric analysis from scientific datasets. • It facilitates the researcher's work, increasing the assertiveness in scientific production.

The control of fungal species in agriculture is mainly conducted with the use of contact or systemic fungicides. However, environmental and human health concerns and increased resistance of fungal species to existing fungicides have increased the pressure on researchers to find new active ingredients for fungal control which present low toxicity to non-target organisms, are environmentally safe, and can be applied at very low concentrations. It is herein described the synthesis of eleven glycerol triazole containing compounds (ten of them fluorinated derivatives) and evaluation of their fungicidal activity. Eight out of eleven synthesized compounds are novel and all of the glycerol derivatives were characterized using infrared (IR), nuclear magnetic ressonance (NMR), and mass spectrometry (MS) techniques. Theoretical calculations were also carried out and the results are discussed. Starting from glycerol, the triazole derivatives were prepared in four steps. Evaluation of them against Colletrotricum gloesporioides showed that compound 1-((2,2-dimethyl-1,3 dioxolan-4-yl)methyl)-4-(2-fluorophenyl)-1H-1,2,3-triazole (4d) (ED50 = 59.14 µg mL-1) was slightly more active than commercial fungicide tebuconazole (61.35 µg mL-1). Compound 4d presented attractive physicochemical features for agrochemical purposes as revealed by the calculated physicochemical parameters. It is believed that glycerol-fluorinated triazole derivatives can be explored towards the development of new chemicals for the control of fungal species.

Abstract The control of weeds in agriculture is mainly conducted with the use of synthetic herbicides. However, environmental and human health concerns and increased resistance of weeds to existing herbicides have increased the pressure on researchers to find new active ingredients for weed control which present low toxicity to non-target organisms, are environmentally safe, and can be applied at low concentrations. It is herein described the synthesis of glycerol-fluorinated triazole derivatives and evaluation of their phytotoxic and cytogenotoxic activities. Starting from glycerol, ten fluorinated triazole derivatives were prepared in four steps. The assessment of them on Lactuca sativa revealed that they present effects on phytotoxic and cytogenotoxic parameters with different degrees of efficiency. The compounds 4a, 4b, 4d, 4e, 4i, and 4j have pre-emergent inhibition behavior, while all the investigated compounds showed post emergent effect. Mechanism of action as clastogenic, aneugenic, and epigenetic were observed in the lettuce root meristematic cells, with alterations as stick chromosome, bridge, delay, c-metaphase, and loss. It is believed that glycerol-fluorinated triazole derivatives possess a scaffold that can be explored towards the development of new chemicals for the control of weed species.

Eriocaulaceae is a pantropical family whose main center of biodiversity is in Brazil. In general, the family has about 1200 species, in which phytochemical and biological studies have shown a variety of structures and activities. The aim of this research is to compile the compounds isolated in the Eriocaulaceae family and carry out a computational study on their biological targets. The bibliographic research was carried out on six databases. Tables were built and organized according to the chemical class. In addition, a summary of the methods of isolating the compounds was also made. In the computational study were used ChEMBL platform, DRAGON 7.0, and the KNIME 4.4.0 software. Two hundred and twenty-two different compounds have been isolated in sixty-eight species, divided mainly into flavonoids and naphthopyranones, and minor compounds. The ligand-based virtual screening found promising molecules and molecules with multitarget potential, such as xanthones 194, 196, 200 and saponin 202, with xanthone 194 as the most promising. Several compounds with biological activities were isolated in the family, but the chemical profiles of many species are still unknown. The selected structures are a starting point for further studies to develop new antiparasitic and antiviral compounds based on natural products.

Among the different strategies adopted to improve the quality of Coffea canephora, fermentation is considered a promising technology to modulate the organoleptic characteristics of the beverage. Considering the possibility of providing a change in sensory profile through fermentation, this study aims to evaluate the chemical and sensory changes promoted by carbonic maceration in C. canephora whose effect is still unknown. The study was implemented in anaerobic conditions with different fermentation times (24, 48, 72, 96, and 120 h) and temperatures (18, 28, and 38 °C). The processed grains were subject to sensory analysis and medium infrared spectroscopy. Significant linear functional relationships were observed between total score and temperature for fermentation times of 24, 72, and 96 h and that the total score increased with fermentation temperature. Although a clear connection with sensory results was not observed, infrared analysis was able to point out important correlations with quality through stretches observed in infrared spectrum regions. Thus, there is feasibility of applying the carbonic maceration technique for grain processing of C. canephora.

We study theoretically the amodiaquine-adenine and amodiaquine-guanine adducts formation using Density Functional Theory (B3LYP) and the 6-31G(d) basis set for the geometry optimizations and 6-31+G(d,p) for the analysis of the global indexes: electrophilicity (w), electronic chemical potential (m), hardness (h) and softness (S), based in the Frontier Molecular Orbital Theory – FMO. Local softness for nucleophilic reaction (sk+) sites over guanine was evaluated using Fukui function (f k). We also evaluated the guanine Electrostatic Potential (EP) values using the (MSK) charge scheme. The theoretical calculations had demonstrated that the amodiaquine has greater electronic affinity for the guanine, with irreversible formation of the amodiaquine-guanine adduct, as reported before on a previous experimental work.

Dengue fever is one of the main public health problems in the world. Many mosquitoes have developed resistance to the conventional insecticides used. Thus, the search for vegetable extracts and natural substances as alternative insecticides has increased. In this study, chemometric methods were employed to classify a group of terpenoid and phenylpropanoid compounds with biological activity against the larval of the A. aegypti mosquitoes. The AM1 (Austin Model 1) method was used to calculate a set of molecular descriptors (properties) for the studied compounds. Then, the descriptors were analyzed using the following methods of pattern recognition: Principal Component Analysis (PCA) and Hierarchical Clustering Analysis (HCA). The PCA and HCA methods have shown to be very effective for the classification of the study compounds in two groups (active and inactive). The electronic variables EHOMO-1, EHOMO-2, ELUMO, ELUMO+2, and the structural LogP were used to classify as active and inactive compounds. In most studied compounds, the variables responsible for separating active from inactive compounds were electronic descriptors. Thus, it can be concluded that electronic effects play a fundamental role in the interaction between biological receptor and terpenoid and phenylpropanoid compounds with activity against larval A. aegypti mosquitoes.

The electrochemical behavior of the interaction of amodiaquine with DNA on a carbon paste electrode was studied using voltametric techniques. In an acid medium, an electroactive adduct is formed when amodiaquine interacts with DNA. The anodic peak is dependent on pH, scan rate and the concentration of the pharmaceutical. Adduct formation is irreversible in nature, and preferentially occurs by interaction of the amodiaquine with the guanine group. Theoretical calculations for optimization of geometry, and DFT analyses and on the electrostatic potential map (EPM), were used in the investigation of adduct formation between amodiaquine and DNA.

Dengue fever is one of the main public health problems in the world. Many mosquitoes have developed resistance to the conventional insecticides used. Thus, the search for vegetable extracts and natural substances as alternative insecticides has increased. In this study, chemometric methods were employed to classify a group ofterpenoid and phenylpropanoid compounds with biological activity against the larval of the A. aegypti mosquitoes. The AM1 (Austin Model 1) method was used to calculate a set of molecular descriptors (properties) for the studied compounds. Then, the descriptors were analyzed using the following methods of pattern recognition: Principal Component Analysis (PCA) and Hierarchical Clustering Analysis (HCA). The PCA and HCA methods have shown to be very effective for the classification of the study compounds in two groups (active and inactive). The electronic variables EHOMO-1, EHOMO-2, ELUMO, ELUMO+2, and the structural LogP were used to classify as active and inactive compounds. In most studied compounds, the variables responsible for separating active from inactive compounds were electronic descriptors. Thus, it can be concluded that electronic effects play a fundamental role in the interaction between biological receptor and terpenoid and phenylpropanoid compounds with activity against larval A. aegypti mosquitoes.

A computational quantum chemistry experiment is described of Diels-Alder reactions between 2-cycloenones and cyclopentadiene. The effects of FMO-Frontier Molecular Orbitals (HOMO-LUMO) and of the withdrawing nature of substituents at the C=C bond of cycloenones were evaluated. The calculations were made using HF/STO-3G and B3LYP/6-31+G(d,p) methods. The FMO based indexes are in agreement with the experimentally observed reactivity order. NBO - Natural Bond Orbitals - analysis was used to ascertain the effect of C=C substituents on the dienophile reactivity.

Economic and environmental reasons show a trend towards replacing fossil fuels with biofuels such as those from triglycerides. Biodiesel can be obtained from vegetable oils and animal fat through several processes such as transesterification, esterification, usually with methanol, ethanol or through pyrolysis, all of them in the presence of an acid or basis catalyst. The use of solid catalysts in biodiesel production has the following advantages: easy recovery and reuse, thus decreasing process costs and amount of waste generated.1 Some of the problems in the use of solid catalysts are: low concentration of active sites, microporosity, and leaching of active sites.2 Studies aiming at developing methodologies involving hydrated niobium oxide as catalyst in biodiesel production have been carried out by our research group.3,4 Parameters such as the use of assistant solvent to increase the boiling point of the mixture (toluene, ethylene glycol, and DMSO), pre-thermal treatment (calcinations) and catalyst molar concentration were initially assessed in esterification, oleic acid, and methanol reactions. From these studies we could observe that high temperatures and excessive alcohol favor esterification reactions. The best reaction conditions were then used as models and employed in transesterification reactions of soybean oil. DMSO (Dimethyl sulfoxide) was the solvent used to increase the reaction medium temperature without evaporating all the methanol. Transesterification reactions were carried out with soybean oil (0.5 g), methanol (0.85 g), DMSO (2.50 ml), and hydrated niobium oxide as catalyst in ratios of 20% and 100% (in relation to oil mass). Catalyst was employed without pretreatment and after pretreatment at 115 °C, 300 °C, and 500 °C. The reactions occurred at 170 °C, under reflux for 48 hours. A reaction without a catalyst was also carried out. All the reactions have shown conversion using CCD and they have been determined by 1H NMR spectroscopy.

We have found that some of the usually poor dienophiles (2-cycloenones) can undergo Diels-Alder reaction at -78°C with unusually high stereoselectivity in the presence of niobium pentachloride as a Lewis acid catalyst. A remarkable difference in reaction rates for unsubstituted and α- or β-methyl substituted 2-cycloenones was also observed.