Publications by authors named "Alysson Duarte Rodrigues"

Activated carbons (ACs) were prepared from dried spent coffee (SCD), a biological waste product, to produce adsorbents for methylene blue (MB) and methyl orange (MO) from aqueous solution. Pre-pyrolysis activation of SCD was achieved via treatment of the SCD with aqueous sodium hydroxide solutions at 90 °C. Pyrolysis of the pretreated SCD at 500 °C for 1 h produced powders with typical characteristics of AC suitable and effective for dye adsorption.

View Article and Find Full Text PDF
Article Synopsis
  • Forward osmosis (FO) is gaining popularity for sustainable water desalination, but it struggles with finding effective, recyclable draw solutes.
  • Researchers created ionosilica hydrogels using quaternary ammonium halides, which displayed efficiency in generating significant osmotic pressure (up to 10.0 atm).
  • While the hydrogels can be regenerated through ultrafiltration for a closed FO-UF process, their osmotic performance declines over time, possibly due to anion exchange issues.
View Article and Find Full Text PDF

A straightforward access to π-conjugated oligothiophenes bearing amino-rich groups was developed. Palladium-catalyzed C-H arylation applied in the main step of the synthesis allowed to couple 2-thiophenecarbonitriles and aryl bromides with moderate to excellent yields (35-93%). Then, to improve their basic fluorescence properties, these compounds were transformed into their 2,4-diamino-1,3,5-triazine derivatives, also with good to excellent yields (74-98%).

View Article and Find Full Text PDF

Solvothermal reaction in N,N-dimethylformamide (DMF) between 1,6-bis(1-imidazolyl)-2,4-hexadiyne monohydrate (L1⋅H O), isophthalic acid (H L2), and Zn(NO ) ⋅6 H O gives the diacetylene-based mixed-ligand coordination polymer {[Zn(L1)(L2)](DMF) } (UMON-44) in 38 % yield. Combination of DSC with variable-temperature single-crystal X-ray diffraction revealed the occurrence of two phase transitions spanning the ranges 129-144 K and 158-188 K. Furthermore, the three structurally similar phases of UMON-44 show giant negative and/or colossal positive thermal expansions.

View Article and Find Full Text PDF

Background: Prion diseases are characterized by the accumulation in the central nervous system of an abnormally folded isoform of the prion protein, named PrP(Sc). Aggregation of PrP(Sc) into oligomers and fibrils is critically involved in the pathogenesis of prion diseases. Oligomers are supposed to be the key neurotoxic agents in prion disease, so modulation of prion aggregation pathways with small molecules can be a valuable strategy for studying prion pathogenicity and for developing new diagnostic and therapeutic approaches.

View Article and Find Full Text PDF