Polypropylene (PP) has been widely used industrially in several sectors, mainly in the use of packaging of different products. Thus, this has been accumulated in our environment due to the incorrect disposal and its high resistance toward degradation, causing an array of environmental impacts. With this, one alternative that has been explored to minimize the problems intensified by these residues is the use of pro-degrading additives. Therefore, the aim of this work is to evaluate the degradation process of PP blends in soil using enzymatic additive. The soil degradation experiment was done for 6 months; monthly collected samples were checked for alterations on the material properties during that time. The extent of PP degradation with enzymatic additive was compared to an organic additive by techniques of FTIR, TGA, DSC, carbonyl index (CI), and crystallinity. From the obtained results it was observed that the additives influenced the degradation of PP. In addition, the enzymatic additive caused more significant changes in the CI (increase of 3693%), crystallinity (variation of 18.7%), and structural characteristics, indicating a greater influence on the degradation process in relation to the organic additive. In this way, this work has had an important role in the research and development of biodegradable materials with the aim of minimizing the effects induced by plastic waste in the environment.

Due to the declining of oil reserves in the world in the coming decades, gas hydrate (GH) is seen as the great promise to supply the planet’s energy demand. With this, the importance of studying the behavior of GH, several researchers have been developing different systems that allow greater truthfulness in relation to the conditions where GH is found in nature. This work describes a new system to simulate formation (precipitation) and dissociation of GH primarily at natural conditions at deep-sea, lakes, and permafrost, but also applied for artificial gas hydrates studies (pipelines, and transport of hydrocarbons, CO2, and hydrogen). This system is fully automated and unique, allowing the simultaneous work in two independent reactors, built in Hastelloy C-22, with a capacity of 1 L and 10 L, facilitating rapid analyses when compared to higher-volume systems. The system can operate using different mixtures of gases (methane, ethane, propane, carbon dioxide, nitrogen, ammonia), high pressure (up to 200 bar) with high operating safety, temperature (−30 to 200 °C), pH controllers, stirring system, water and gas samplers, and hyphenated system with gas chromatograph (GC) to analyze the composition of the gases formed in the GH and was projected to possibility the visualizations of experiments (quartz windows).

This article aims to perform a qualitative analysis on the questions produced by the visitors of the activity "Magic or Science?" of event Portas Abertas offered by a Brazilian public university. In event Portas Abertas of 2018, six experiments were presented to more than 100 visitors who interacted with the moderators through questions about practices. Therefore, the objective of this article is to analyze the character and the demand of the questions asked by the visitors of the activity and to classify them according to the components of the scientific explanation proposed in the literature. The questions produced were recorded with a voice recorder and in the researchers' field diaries. In general, there was a predominance of informative questions belonging to the subcategories of description and causal explanation, however it is highlighted that there was a satisfactory number of investigative questions of prediction. The questions classified with the investigative character and demand of the prediction type need a future action to be answered, that is, they favor the investigation on the scientific knowledge involved in the studied phenomenon.

Carbon dioxide capture, storage, and transport technology based on the formation of gas hydrate is an innovative solution. In this work, the experimental investigations on the formation of CO2 hydrates were carried out with aqueous solutions containing 0.5% by weight of three different organic salts synthesized from l-phenylalanine and different alcohols under isochoric conditions. All of the synthesized compounds were obtained with good yields (74.2–87.7%), and among them, the nonyl l-phenylalanine hydrochloride is an unprecedented compound. In addition, there has not been any study with organic salts aiming to verify their influence as an inhibitor or promoter of CO2 hydrates. The compound pentyl l-phenylalanine hydrochloride showed a successful result in promoting CO2 hydrate since it achieved a shorter induction time (1.74 h), a higher CO2 consumption rate, and better storage capacity (slope of the pressure curve). In addition, dodecyl l-phenylalanine hydrochloride has the characteristic of CO2 hydrate inhibitor, and therefore it was observed that the increase of the side-chain hydrophobicity (carbon chain linked to the oxygen function of the ester function) provides the effect of inhibiting CO2 hydrates.

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