<p>As questões ambientais têm ocupado cada vez mais espaço nas legislações dos países, devido à grande geração de resíduos, oriundos principalmente, da indústria da construção civil. Para qualquer país, não tem como haver crescimento, sem que a indústria da construção o acompanhe. Crescimento este, que gera grandes impactos ambientais, desde a extração de recursos naturais para a produção de insumos, até a produção de resíduos, que são dispostos no meio ambiente sem nenhum controle. Este artigo expõe pesquisas que retratam a preocupação quanto à geração dos resíduos provenientes da indústria da construção não somente no Brasil, mas em todo o mundo. Pesquisadores de todo o planeta disponibilizam dados quanto à quantidade de RCD gerado, legislações empregadas com o intuito de minimizar e prevenir a geração de RCD e aplicabilidades dos resíduos reciclados nos mais diversos ramos do setor construtivo, de forma a promover o seu retorno à cadeia da construção. Dados estes, que foram apresentados neste trabalho, com o intuito de "acordar" o Brasil, para a nova ordem mundial, em que a palavra <bold>reciclar</bold>, não mais será uma opção, e sim, rotina de cada brasileiro.</p>

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Corner-truncated cubic β-Ag 1.94 Cu 0.06 MoO 4 microcrystals were synthesized using the hydrothermal method. These were investigated by X-ray diffraction, confirming obtention of the spinel structure Fd3̅ m. Through Raman spectroscopy are confirmed all modes for the point group of O h 7. The E gap shows a decrease of the band gap from 3.20 to 3.07 eV, with reduction of the conduction band occurring from −0.20 eV (β-Ag 2 MoO 4 ) to −0.13 eV (β-Ag 1.94 Cu 0.06 MoO 4 ), suggesting a p-type behavior for the Cu 2+ ion. The fieldemission scanning electron microscopy images confirm the morphological changes for β-Ag 2 MoO 4 , where potato-like microcrystals were found. Meanwhile, corner-truncated cubic microcrystals for β-Ag 1.94 Cu 0.06 MoO 4 . The photoluminescence (PL) spectrum confirms the increase in the PL emission for β-Ag 1.94 Cu 0.06 MoO 4 , with suppression of the deep defects occurring in the structure caused by oxygen and silver atoms. In contrast, the green region is intensified because of distortions of the Ag−O and Mo−O bonds. Therefore, the β-Ag 1.94 Cu 0.06 MoO 4 solid solution has PL emission with CCT (4510 K) and CIE coordinates (x = 0.372 and y = 0.433), which could be interesting properties for applications as light-emitting diodes.

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Olefin metathesis is a crucial reaction typically catalyzed by Mo and Ru metal-carbene complexes. Catalysts based on 3d metals have recently attracted much interest due to their abundance, low toxicity, and inexpensive cost. Recently prepared vanadium-carbene complexes with analogous ligands to those of the Schrock carbenes were shown to be effective catalysts for norbornene's ring-opening metathesis polymerization (ROMP). In this work, we employ density functional theory (B3LYP) calculations to explore the reaction mechanism and the energetic performance of the V V (CHSiMe 3 )(NC 6 H 5 )[OC(CF 3 ) 3 ]-(PMe 3 ) 2 (D) complex in catalyzing the ROMP of norbornene. Calculations revealed that the reaction takes place in the singlet spin surface through the classical olefin metathesis mechanism. The electronic analysis indicates the absence of valence electrons in the metallic vanadium d 0 center as a cause in favoring the singlet spin state. The deactivation pathways toward cyclopropanation and βhydride elimination were calculated, and they showed higher barriers than those for olefin metathesis. The replacement of the carbene substituent −SiMe 3 by the substituent −CMe 3 was also analyzed, showing no considerable differences regarding previous catalysts. Our results suggest that the cross-metathesis reaction of styrene catalyzed by the D complex is viable since it presented a potential energy surface similar to that observed in the ROMP reaction of norbornene. The potential energy surfaces of the ROMP reaction catalyzed by D and a Schrock catalyst indicate that the classic molybdenum catalyst favors lower energy barriers compared to vanadium catalysts.