Assessment of the mechanical and physical characteristics of PET bricks with different aggregates.

Construction and demolition waste, along with discarded PET plastic bottles, have evolved into a widespread global resource. However, their current disposal in landfills poses a significant environmental pollution challenge. This research is centered on evaluating the performance of cement mortar composed by larger PET particles in conjunction with sand, construction and demolition waste, and lightweight expanded polystyrene aggregates.

Unzipping nucleoside channels by means of alcohol disassembly.

Gold nanoparticles capped with simple adenosine derivatives can form colloidal aggregates in nonpolar solvents. Theoretical calculations indicate the formation of organic channels by the supramolecular assembly of the nanoparticles by means of hydrogen bonds between the adenine moieties. The aggregates were only negligibly sensitive to nPrOH, iPrOH, and tBuOH, whereas some showed a similar response to MeOH and EtOH, and others showed high selectivity toward MeOH.

Experimental and computational study of 6-exo and 7-endo cyclization of aryl radicals followed by tandem S(RN)1 substitution.

The reaction of N-allyl-N-(2-halobenzyl)-acetamides and derivatives was investigated in liquid ammonia under irradiation with the nucleophiles Me3Sn(-), Ph2P(-) and O2NCH2(-). Following this procedure, novel substituted 2-acetyl-1,2,3,4-tetrahydroisoquinolines and substituted 2-acetyl-2,3,4,5-tetrahydro-1H-benzo[c]azepines were obtained in good yields. These reactions are proposed to occur through the intermediacy of aryl radicals, which by intramolecular 6-exo or 7-endo attack to a double bond cyclize to give aliphatic radicals, which react along the propagation steps of the S(RN)1 chain cycle to afford the cyclic substituted compounds as main products.

Nucleophilic substitution of bromonorbornenes and derivatives by electron transfer reactions.

The photoinitiated substitution reactions of anti-7-bromobenzonorbornadiene (5), its syn isomer 6, exo-anti-13-bromobenzocyclobutanorbornene (7), syn-7-bromonorbornene (8) and bromonorbornane (9) with Me(3)Sn(-) and Ph(2)P(-) anions, in liquid ammonia, are here informed to occur with good yields of substitution. The stereochemical outcome is discussed in terms of calculations with the B3LYP functional and the 6-31+G* basis set; the solvent being included as a continuum through the PCM model. The experimental relative chemical reactivity of pairs of substrates toward a given anion is also presented.