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The paper deals with the application of microalgae in building's façade, regard to the broader project comprising the aspects of the environmental comfort of academic spaces and the energy consumption with on-grid photovoltaic generation, as well as the investigation of alternatives for the improvement of the performance of the building envelopes. Thus, its main objective is the application of interdisciplinary concepts involving Architecture and Biotechnology, as known by Black Ecologies, referring to an investigative interest to explore a new approach of nature, not only related to architectural space, but an emergent environmental focus. This relationship is performed by using photobioreactors with microalgae, installed on the façades of buildings for educational use. The present work presents the methodological outline of the research, based on literature review and case studies; complementary experimental methodologies are also presented to contextualize the subject and its application and feasibility. The current state of art showed an emergent approach in terms of international level, but in the Brazilian context any further research was identified yet. In addition to thermal and energy performance, the strategies will allow the process of sequestration of carbon dioxide and other GHG (greenhouse gases) that impacts on the process of climate change and can contribute to reach the sustainable development. This subject coincides with the discussions of the 2050 scenarios and emission reduction, which were faced at the recent COP-27 and its connections with an integrative way to contribute to the United Nations Sustainable Development Goals. [ABSTRACT FROM AUTHOR]

Ice-infiltrated sediment, or frozen fringe, is responsible for phenomena such as frost heave, ice lenses and metres of debris-rich ice under glaciers. Understanding frozen fringes is important as frost heave is responsible for damaging infrastructure at high latitudes and sediment freeze-on at the base of glaciers can modulate subglacial friction, influencing the rate of global sea level rise. Here we describe the thermomechanics of liquid water flow and freezing in ice-saturated sediments, focusing on the conditions relevant for subglacial environments. The force balance that governs the frozen fringe thickness depends on the weight of the overlying material, the thermomolecular force between ice and sediments across liquid premelted films and the water pressure required by Darcy flow. We combine this mechanical model with an enthalpy method that conserves energy across phase change interfaces on a fixed computational grid. The force balance and enthalpy model together determine the evolution of the frozen fringe thickness and our simulations predict frost heave rates and ice lens spacing. Our model accounts for premelting at ice–sediment contacts, partial ice saturation of the pore space, water flow through the fringe, the thermodynamics of the ice–water–sediment interface and vertical force balance. We explicitly account for the formation of ice lenses, regions of pure ice that cleave the fringe at the depth where the interparticle force vanishes. Our model results allow us to predict the thickness of a frozen fringe and the spacing of ice lenses in subaerial and subglacial sediments. [ABSTRACT FROM AUTHOR]

Small quantities of liquid water lining triple junctions in polycrystalline glacier ice form connected vein networks that enable material exchange with underlying basal environments. Diffuse debris concentrations commonly observed in ice marginal regions might be attributed to this mechanism. Following recent cryogenic ring-shear experiments, we observed emplacement along grain boundaries of loess particles several tens of microns in size. Here, we describe an idealized model of vein liquid flow to elucidate conditions favoring such particle transport. Gradients in liquid potential drive flow toward colder temperatures and lower solute concentrations, while deviations of the ice stress state from hydrostatic balance produce additional suction toward anomalously low ice pressures. Our model predicts particle entrainment following both modest warming along the basal interface resulting from anticipated natural changes in effective stress, and the interior relaxation of temperature and solute concentration imposed by our experimental protocols. Comparisons with experimental observations are encouraging, but suggest that liquid flow rates are somewhat higher and/or more effective at dragging larger particles than predicted by our idealized model with nominal parameter choices. Diffuse debris entrainment extending several meters above the glacier bed likely requires a more sophisticated treatment that incorporates effects of ice deformation or other processes. [ABSTRACT FROM AUTHOR]