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  • Open access
  • 64 Reads
Metal-doped copper indium disulfide heterostructure: Environment-friendly Hole-transporting material toward photovoltaic application in organic-inorganic perovskite solar cell

Recently, by increasing global warming, reducing fossil fuels and increasing greenhouse gas emissions, generation of green energy through the development of renewable energy sources to provide the human energy needed is great importance. Generally, among the various sources of renewable energy, such as: solar, wind, natural gas and geothermal, sun energy is the most unique source to green energy in the future due to its abundance, ubiquity, unlimited, eco-friendly, low cost fabrication, clean and easy access. In organic-inorganic perovskite solar cells (PSCs), the CH3NH3PbI3 active layer is sandwiched between the electron-transport layer (ETL) and hole-transporting layer (HTL). The common HTL and in order to are spiro MeOTAD and TiO2, in sequence, were used. As well as the ETL and HTL systems and play considerable roles in photovoltaic parameters of the PSCs. In this plan, a metal with copper indium disulfide (CIS), to doped through the heterostructure system, were synthesized. And its Application of this heterostructure as the HTL system was investigated in the fabrication of the organic-inorganic PSCs.

  • Open access
  • 73 Reads
Synthesis, Characterization and Evaluation of a Novel BODIPY Derivative as a Colorimetric Chemosensor for Fe3+ Recognition

BODIPY derivatives have been proving to be a key class of compounds as a tool for a wide range of research fields. Among the diverse applications of BODIPYs, the development of derivatives owning the ability to recognize and detect small organic molecules and metal ions have received great attention in the last years. Moreover, the BODIPY core can be chemically modified in order to improve the optical properties or add new functionalities as chemosensors, for example insertion of receptor groups selective to analytes. There are diverse cations with biological and environment relevance, such as Fe3+ as an important metal ion in several physiological process involving electron transfer, oxidation and also as an enzymatic cofactor for oxygen transport, DNA synthesis, etc. On the other hand, the accumulation of iron in the central nervous system has been implicated in a number of diseases. Therefore, the design of molecular systems for recognition of cations with ‘‘naked-eye’’ detection is an attractive goal.In continuation of our research group’s investigation developed in the field of chromofluorogenic sensors, we report in this work the synthesis, characterization and evaluation of a novel BODIPY derivative as a colorimetric chemosensor for Fe3+ recognition in acetonitrile solution.

  • Open access
  • 59 Reads
Beetroot as a source of natural dyes for ham

Due to the composition and processing of leg ham, in some cases the final color is not the most attractive. Legislation does not allow the use of synthetic dyes and even natural dyes presently used in other food products.

Beetroot (Beta vulgaris L.) possess water soluble betalain pigments and its use as an ingredient in several products imparts beneficial effects on human health.

Considering these facts, Beta vulgaris L. was subjected to extraction procedures in order to obtain the respective extracts containing the natural dyes, and subjected to cytotoxicity assays in AGS cell line. Encapsulation of the extracts in nanosystems based on soybean lecithin and maltodextrin was performed. Lyophilized extracts before and after encapsulation in maltodextrin were applied in the formulation of leg ham and used in pilot scale of production. The color of ham samples from the different assays was evaluated visually and by colorimetry.

The results show that leg ham coloration obtained using lyophilized extracts of Beta vulgaris L. is very promising for future applications in this type of meat products.

  • Open access
  • 69 Reads
Characterization and photocatalytic degradation of methyl orange in water by Ni0.1Cu0.1Zn0.8Fe2O4 nanoparticles synthesized by gel-auto combustion and microwave-assisted methods

Over the past few decades, magnetic nanoparticles have been considered by many researchers due to their unique physicochemical, magnetic and optical properties and extensive applications in the field of biomedical (such as magnetic resonance imaging (MRI), drug delivery system and magnetic hyperthermia), catalysis, information technology, telecommunication and environmental remediation, destruction of organic pollutants such as dyes, etc. In this work, it has been attempted to synthesize Ni0.1Cu0.1Zn0.8Fe2O4 by both gel-auto combustion and microwave-assisted methods and the resulting powders were characterized by different analysis involved, XRD, SEM, IR, EDS, VSM and UV-Vis spectra. The effect of these two ferrites on the absorption and degradation of methylene orange dye was studied at different concentrations (100, 160 and 200 ppm). The average crystalline size of MNPs obtained by gel-auto combustion and MW-assisted, were 77.9 and 44.1 nm, respectively. The specific magnetization curves exhibit ferromagnetism of soft magnetic materials and the (Ms) values of samples were 20.64 and 52.89 (emu/g) for MNPs obtained by gel-auto combustion and MW-assisted, respectively. Finally, both ferrites showed high absorption of methylene orange dye in water under UV-Vis irradiation (λ> 400 nm).

  • Open access
  • 111 Reads
Asymmetric Biginelli-like reaction catalyzed by chiral TADDOL-derived phosphoric acid bearing two hydroxyl groups

Several new chiral TADDOL-derived phosphoric acids bearing two hydroxyl groups have been successfully synthesized via highly regioselective 2,3-cyclosulfitation as asymmetric catalysts for Biginelli-like reaction. The obtained results clearly demonstrated that these catalysts are able to effectively catalyze the reactions with good to excellent enantioselectivities. A control experiment indicated that two hydroxyl groups are indispensable for high enantioselectivity of the Biginelli-like reaction.

  • Open access
  • 66 Reads

Schinus areira L. is a native species known by its medicinal value. It originates from the NW of Argentina and it is commonly known as ‘Aguaribay’. This study aims to evaluate the broad spectrum of antioxidant, antimutagenic and antipromutagenic activities of Schinus areira L leaves essential oil (EO) and one of its components, globulol. The chemical composition of the EO obtained by hydrodistillation was determined by GC-MS, and fractionated by RP-HPLC. The active compound (16.61%) isolated was identified by comparison of its 1H and 13C NMR data with those reported in the literature.

The antimutagenic and antipromutagenic activities were evaluated in vitro and ex vivo, using the Ames assay with five strains of Salmonella typhimurium with and without exogenous metabolic activation (rat liver fraction S9), against different mutagens. The result determined that globulol and EO of S. areira at the applied doses do not exhibit any mutagenic effect and showed highest antioxidant activity.

In summary, the mutagenicity assay show that none of the samples induced any increase in the number of revertant colonies on the strains tested, either in the presence or absence of metabolic activation, indicating the absence of any mutagenic activity. These activities may be associated with the presence of antioxidant compounds, as globulol in the EO. The EO and globulol were able to reduce or inhibit DNA damage or mutations induced by cancer cells and disease caused by genotoxic agents.

  • Open access
  • 158 Reads
Chemical recycling: comparative study about the depolymerization of PET waste-bottles to obtain terephthalic acid.

Currently, the plastic packaging industry in Brazil is the second largest producer in the packaging sector, with approximately 35% of the total packaging produced per year. Out of this total, 572 thousand tons are composed of polyethylene terephthalate plastic bottles (PET).

In the ranking of the main materials discarded in the country, plastic occupies the third position and, in most cases, inadequately. The recycling industries are growing constantly seeking to reuse the materials and reduce the impacts caused by this inadequately discard, even so, it’s not enough to switch back. Not even a newly discovered bacterium (Ideonella sakaiensis 201-F6), which is capable of metabolizes that polymer, can be seen as an immediately solution, because the processes are not already optimized or sized for such a large volume of PET.

Objectifying minimizes the amount of PET packaging improperly discarded and to instigate the industrial interest in the subject, our work pursued a viable path, as clean as possible in the principles of Green Chemistry, to depolymerize it. Obtaining the terephthalic acid as the main product, which is commercially obtained by oil sources and using salts and oxide of zinc as catalyzers in water as solvent, besides using inorganic bases as catalyzers in alcohols as solvent, including glycerol, which is a sub product of Biodiesel Industries. The reactions were made by refluxing (traditional way) and by microwave, where was used the reactor Biotage Initiator Plus. The products were characterized by Fourier Transformed Infrared Spectroscopy (FTIR of Bruker) and Ultra Performance Liquid Chromatography with Mass Spectrometer with Electrospray Ionization (UPLC-ESI/MS), where the results were better while using zinc sulfate as catalyzer in water and potassium hydroxide as catalyzer in pentan-1-ol.

  • Open access
  • 63 Reads
Extraction and physicochemical characterization of chitin derived from the Asian hornet, Vespa velutina Lepeletier 1836 (Hym.: Vespidae)

The yellow-legged Asian hornet [Vespa velutina Lepeletier 1836 (Hymenoptera: Vespidae)] is naturally distributed in Southeast Asia, India, and China; however, fifteen years ago, at least one multimated female Asian hornet arrived in France. The species has subsequently expanded its range and is now presently recognized as a pan-European threat. In the present work, the isolation and characterization of chitin from Vespa velutina (VV) is described. Moreover, a trapping procedure is presented to selectively catch the invasive insect. The physicochemical properties of chitin obtained from the VV was characterized by Fourier transform infrared spectroscopy (FTIR), solid-state NMR (ssNMR), elemental analysis (EA), scanning electron microscopy (SEM) and thermogravimetric analysis (TG). Also, lifetime and kinetic parameters such as activation energy (E) and the prexponential factor (A) were calculated using model-free and model-fitting methods. Results obtained show the invasive VV as a large-scale and perspective source of chitin/chitosan. Based on the quality of the obtained product, chitin isolated from VV is a promising alternative source of chitin in terms of utilization and applications, in various fields such as biomedical, nanotechnological, pharmaceutical and food areas.

  • Open access
  • 81 Reads
Synthesis of Imidazo[1,2-a]pyridine-chromones via ultrasound-assisted Groebke-Blackburn-Bienaymé Reaction

A serie of imidazo[1,2-a]pyridine-chromones were synthesized by ultrasound-assisted Groebke–Blackburn–Bienaymé reaction (GBBR) under eco-friendly conditions (20 mol% ammonium chloride catalyst in EtOH). Chromones and imidazo[1,2-a]pyridines are a privileged class framework of high interest in medicinal chemistry because they are present in numerous compounds showing relevant biological activities.