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- Estudo exploratório do aproveitamento de águas pluviais numa escola do campus do IPSPublication . Gamelas ou Carla A. Gamelas, Carla; Lucas, Susana; Abreu, Soraia; Alegria, Jessica; Figueira, Glória; Jesus, Daniel
- Oxido-bis¬[chlorido(4,4'-di-tert-butyl-2,2'-bipyridine-2N,N')dioxido¬molybdenum(VI)] 0.2-hydratePublication . Gomes, A. C.; Fernandes, J. A.; Gamelas ou Carla A. Gamelas, Carla; Gonçalves, I. S.; Almeida-Paz, F. A.The title hydrate, [Mo2Cl2O5(C18H24N2)2]·0.2H2O, has been isolated as the oxidation product of [Mo(3-C3H5)Cl(CO)2(di-t-Bu-bipy)] (where di-t-Bu-bipy is 4,4'-di-tert-butyl-2,2'-bipyridine). A -oxide ligand bridges two similar MoCl(di-t-Bu-bipy)O2 units, having the terminal oxide ligands mutually cis, and the chloride and -oxide trans to each other. In the binuclear complex, the coordination geometries of the metal atoms can be described as highly distorted octahedra. Individual complexes co-crystallize with a partially occupied water molecule of crystallization (occupancy factor = 0.20; H atoms not located), with the crystal packing being mediated by the need to effectively fill the available space. A number of weak C-HO and C-HCl interactions are present.
- Impact of wood combustion in fireplaces on indoor air qualityPublication . Ascenção, J.; Martins, V.; Gamelas ou Carla A. Gamelas, Carla; Almeida, S. M.
- The impact of COVID-19 confinement measures in the Air Quality in an urban-industrial zone in PortugalPublication . Abecassis, Leonor; Gamelas ou Carla A. Gamelas, Carla; Canha, Nuno; Almeida, Susana MartaThis work aims to evaluate the temporal evolution of the concentrations of pollutants PM10, NO2 and O3, from 2001 to 2020, and to evaluate the impact of the COVID-19 pandemic on the levels of these atmospheric pollutants, in an urban-industrial zone (Paio Pires-Seixal, Portugal). The results showed that a significant improvement in air quality resulted from the large restriction of anthropogenic activities that occurred due to the pandemic, namely the March-May 2020 lockdown. The mean concentrations of PM10, NO2 and O3 in 2020 were compared with the average concentrations measured from 2014 to 2019. The most expressive reduction in NO2 (-43.9%, p=0.000) was found in April 2020, when a very expressive PM10 reduction was also registered (- 40.0%, p=0.000) and significant reductions of both pollutants were found in the months thereafter.
- Selective preparation of campholenic aldehyde using indenyl Molybdenum dicarbonyl complexesPublication . Bruno, Sofia; Gamelas ou Carla A. Gamelas, Carla; Gomes, Ana C.; Valente, Anabela; Pillinger, Martyn; Romão, Carlos C.; Gonçalves, isabel S.
- Chemoselective Sulfide and Sulfoxide Oxidations by CpMo(CO)3Cl/HOOR: a DFT Mechanistic Study. OrganometallicsPublication . Veiros, Luís; Gamelas ou Carla A. Gamelas, Carla; Calhorda, Maria José; Romão, CarlosThe mechanism of sulfide and sulfoxide oxidation with peroxides (ROOH, R = H, Me), catalyzed by Mo(VI) complexes, was investigated by means of DFT/PBE1PBE calculations. Two different catalytic systems were considered: the first is based on the dioxocyclopentadienyl (Cp) complex CpMoO2Cl (Cp = η5-C5H5), also active as a catalyst for olefin epoxidation, and the second based on MoO2Cl2. The most favorable mechanism in the Cp system is initiated by the O−H activation of the HOOR oxidant, which in the presence of CpMoO2Cl leads to formation of CpMoO(OH)(OOR)Cl. Although this is the active species for olefin epoxidation, an alternative pathway with lower energy is available. With the crucial H-bond assistance of another oxidant molecule, the oxoperoxo complex CpMoO(O2)Cl forms, with release of alcohol ROH as byproduct and a calculated energy barrier below 25 kcal mol−1. The mechanisms unveiled for sulfide to sulfoxide oxidation and for sulfoxide to sulfone oxidation are equivalent in their general features and follow outer-sphere mechanisms with S-nucleophilic attack from a free molecule of substrate (sulfide or sulfoxide) to the peroxide which is activated through Mo−O coordination. The MoO2Cl2 catalyst follows a similar course, calculated from MoO2Cl2(H2O)(H2O2). Again, explicit consideration of one molecule of solvent (water) proved essential to facilitate the H-transfer processes involved in the mechanism. The highest energy barrier calculated (ca. 25 kcal mol−1) corresponds to a H shift from the Oα to the Oβ atom of the coordinated H2O2 molecule, activating Oα for the oxidation reaction and preparing water (H2Oβ) as the future leaving group. The outer-sphere mechanism ends with coordination of the oxidation product.
- Volatile Organic Compounds in Healthcare facilities - A study developed in Primary Healthcare Centers in LisbonPublication . Viegas, S.; Almeida, B.; Gamelas ou Carla A. Gamelas, Carla; Carolino, E.; Viegas, C.
- Chiral Mo and W Complexes bearing Oxazoline-Cyclopentadienyl LigandsPublication . Reis, P.; Gamelas ou Carla A. Gamelas, Carla; Brito, J.; Goméz, M.; Royo, B.
- Intercalation of a molybdenum η3-allyl dicarbonyl complex in a layered double hydroxide and catalytic performance in olefin epoxidationPublication . Gomes, Ana C.; Bruno, Sofia M.; Gamelas ou Carla A. Gamelas, Carla; Valente, Anabela A.; Abrantes, Marta; Gonçalves, Isabel S.; Romão, Carlos C.; Pillinger, Martyn
- Chiral Molybdenum and Tungsten Complexes Bearing Oxazoline-Derived Cyclopentadienyl LigandsPublication . Reis, Patrícia; Gamelas ou Carla A. Gamelas, Carla; Brito, José; Goméz, Monserrat; Royo, Beatriz