Navegando por Assunto "Gases de efeito estufa"

Agora exibindo 1 - 2 de 2

Acesso aberto (Open Access)
Dinâmica dos fluxos de dióxido de carbono e metano em área de várzea e terra firme do estuário Amazônico
(Universidade Federal do Pará, 2022-04-29) FLORES ARONI, Mario; JARDIM, Mário Augusto Gonçalves; http://lattes.cnpq.br/9596100367613471; https://orcid.org/0000-0003-1575-1248; CATTANIO, José Henrique; http://lattes.cnpq.br/1518769773387350; https://orcid.org/0000-0001-8335-9593
Terrestrial ecosystems are important for the greenhouse gases exchange (GHG) between the surface and the atmosphere. The objective of this research was to investigate the annual dynamics of carbon dioxide (FCO2) and methane (FCH4) fluxes in different environments, in relation to floristic composition and environmental variables in a floodplain area of the Amazon estuary. The flux of greenhouse gases (GHG) was simultaneously measured in the terrestrial and aquatic environment, in a tidal cycle, during few days in the year. This study also included a seasonal comparison of GHG fluxes in açaí planted in an upland area compared to an açaí managed area in the floodplain of the Amazon estuary. The floodplain study was carried out in the Environmental Protection Area of Combú Island (APA Combú), Belém, Pará (Brazil), between 2019 and 2021. The study in the upland area was carried out in Santa Maria do Pará. The methodology to measure soil and water FCO2 and FCH4 consisted of closed dynamic chamber and floating chambers methodology, respectively. The Amazonian estuaries showed topographic variability reflected in the water table height, which influences the soil FCO2 and FCH4 dynamics. In the same way that increase in soil temperature contributed to CO2 emissions. Therefore, a possible increase in global temperature could favor CO2 fluxes in the Amazon estuary. The tidal influence in the stream has strong impacts on FCO2 and FCH4 of the water, which play a key role in the carbon cycle through the CO2 and CH4 exchange between water-atmosphere environments. Lowland soils dominated by açaí plantations are a source of CO2 and CH4. However, the advance of açaí plantations in upland is positive for the environmental benefit (CH4 sink).
Acesso aberto (Open Access)
Estudo das ftalocianinas metálicas na adsorção de gases do efeito estufa e poluentes utilizando docagem molecular
(Universidade Federal do Pará, 2025-04-30) SOUSA, José Antonio Ferreira de; OLIVEIRA, Mozaniel Santana de; http://lattes.cnpq.br/0810227136654245; CHAVES NETO, Antonio Maia de Jesus; http://lattes.cnpq.br/3507474637884699
Atmospheric pollution, driven by the emission of toxic gases, represents an environmental and public health challenge. This study investigates the application of phthalocyanines (Pc) and metal phthalocyanines (MPc) of iron (FePc), cobalt (CoPc), copper (CuPc), zinc (ZnPc), and titanium (TiPc) for the capture of gases such as carbon dioxide (CO₂), carbon monoxide (CO), ammonia (NH₃), hydrogen cyanide (HCN), hydrogen sulfide (H₂S), and aromatic compounds like benzene (C₆H₆). AutoDock Vina 1.2.0 and Gaussian 09W were the software employed in the molecular docking technique to investigate these interactions. Gaussian 09W enabled adjustments in atomic positions to minimize the total interaction energy and build the molecular models. AutoDock Vina 1.2.0 facilitated the calculation of the most favorable binding mode between the toxic molecules and the MPc and Pc, providing detailed information on the most stable adsorption positions, orientations, and energies. The analyses indicate that MPc and Pc exhibit the best interactions with C₆H₆, while the weakest coupling occurred with H₂S. Among the evaluated substances, the best binding interactions occurred with MPc, and among them, TiPc proved to be the most efficient, exhibiting the strongest attraction to CO₂. These molecules are highly promising for the capture and elimination of the tested molecules and, consequently, constitute fundamental strategies for protecting the environment, promoting public health, and ensuring sustainable development for future generations.