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Uma luz na escuridão: eclipse solar e pira funerária nas cerimônias fúnebres do imperador romano Otávio Augusto
(2020) Gonçalves, Ana Teresa Marques
The funerary rites developed after the death of Emperor Octavius Augustus, in A.D. 14, mixed traditions with innovations. Just as the form of government he engendered, which amalgamated republican institutions with autocratic provisions, giving rise to the Principatus, the funeral ceremonies carried out with the passing of the Princeps allowed the development of new practices and the old cults. Through the analysis of ample textual material, we noticed the resumption of the occurrence of a solar eclipse, which launched the imperial territory in a period of darkness, as one of the main omina mortis, which preceded and indicated the death of the sovereign. Such darkness was only dissipated with the realization of imperial funerals, with the Emperor’s real or imaginary body consumed in flames on the funeral pyre, which thus guaranteed the return of light and the restoration of balance, abundance and harmony within the Empire. In this article, we propose to reflect on this recurring omen in the disastrous narratives and its connection with the need to suppress the corpse, by burning it, to provide the return of imperial peace, after the death of the main representative of Res Publica, which left the command center empty until a new Prince was chosen.
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Censura e recriação de imagens: Marco Antônio e a manutenção de sua representação como inimigo da Res Publica
(2016) Gonçalves, Ana Teresa Marques; Oliveira, Rodrigo Santos Monteiro
The documents show to historical researcher possibilities of what was the past. We are taken by the point of view of those who described their own time and by the documents that “survived” (with some missing pieces) for many years of existence. For that reason, the mission of a historical researcher who research Ancient Rome it’s very hard, because the temporal distance it’s bigger. Even so, we show on this paper a possible reading of a very controversial character of republican roman history: Mark Anthony. Our intention is realize why his image was pervades of many years in a so negative way and, also, how was the contribution of this memory construction for the valorization of Octavio Augustus image.
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Feasible strategies to promote the sensing performances of spinel MCo2O4 (M = Ni, Fe, Mn, Cu and Zn) based electrochemical sensors: a review
(2021) Goncalves, Josué Martins; Rocha, Diego Pessoa; Silva, Murillo Neia Thomaz da; Martin, Paulo Roberto; Nossol, Edson; Angnes, Lucio; Rout, Chandra Sekhar; Munoz, Rodrigo Alejandro Abarza
Spinel MCo2O4 (M = Ni, Fe, Mn, Cu and Zn) demonstrates excellent physicochemical properties due to the combined effects of M2+ and Co3+ cations. Their inimitable optical, electronic, and mechanical properties open up windows for a broad range of promising applications. The development of novel spinels has opened virtually infinite possibilities for the development of different sensors. The association of nanomaterials with conventional electrodes or other substrates can produce completely novel and high performance sensors. The knowledge about the nanomaterials allows us to tailor sensors for desired applications. In this regard, the spinel MCo2O4 based materials and their composites offer great promise for the design and development of high-performance electrochemical sensors to detect target species in solution or in gas phase. Aiming to shed light on these important materials, this review presents the role of such cobaltites and their composites towards the development of electrochemical sensors with improved analytical properties for sensing in solution as well as gas phase. A critical comparison of the proposed sensors using these MCo2O4-based materials with other chemically-modified sensors considered the best choices in the literature for some target molecules is presented in order to demonstrate the benefits of such materials. Further, future perspectives and opportunities in these exciting research fields are also commented based on their current progress.
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Nanoporous gold-based materials for electrochemical energy storage and conversion
(2021) Gonçalves, Josué Martins; Kumar, Abhishek; Silva, Matheus Ireno da; Toma, Henrique Eisi; Martins , Paulo Roberto; Araki , Koiti; Bertotti, Mauro; Angnes, Lucio
Herein, the promising world of nanoporous gold (NPG) as an electrode material for energy storage and conversion is reviewed. NPG has excellent conductivity and a porous structure, providing a huge active surface area for deposition of transition metal atoms and electrochemically active materials. Moreover, NPG materials display high intrinsic activity because of their crystallographic structural defects to catalyze hosts of electrochemical reactions, considered pertinent in clean energy technologies. Therefore, taking into account their superior specific and mass activity, they provide a versatile platform for developing high-performance catalysts for oxidation and reduction reactions, supercapacitors, and battery-type electrode materials for the assembly of high density electric energy storage devices. Initially, a full overview of the strategies used to build NPG structures and incorporate other metallic elements in the pore walls is presented. Afterward, the water-splitting parameters and performance of NPG catalysts for hydrogen generation are reviewed. Next, the possibility of using such porous materials as fuel cell electrodes is discussed. In short, the most recent advancements in the field paving the way for the preparation of advanced electrode materials meeting the most stringent requirements are reviewed, demonstrating the bright perspectives for innovation in the key area of energy conversion and storage.
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Recent progress in Core@Shell sulfide electrode materials for advanced supercapacitor devices
(2021) Gonçalves, Josué Martins; Silva, Matheus Ireno da; Hasheminejad, Meisam; Toma, Henrique Eisi; Araki, Koiti; Martins, Paulo Roberto; Angnes, Lucio
Highly conductive and surface area complex hierarchical 3D core@shell nanostructures made of multi-metallic multi-valence sulfides are being specially designed as electrode materials of high performance and high power supercapacitors. In fact, bimetallic and trimetallic sulfides have outstanding redox properties as compared with the corresponding single-phase sulfide based materials, and much higher electrical conductivity than the analogue oxide materials, being excellent materials for the design of core@shell structures with exceptional charge capacity, power, and energy performance. For this purpose, the core material should exhibit high charge diffusion rates and large specific capacitance, while the shell should improve the surface area by promoting a greater accessibility to the electroactive sites thus maximizing the charge capacity and conductivity. In this context, a rational design of nanostructured materials encompassing advanced 2D materials (such as graphene, MXene, black phosphorus, transition metal hydroxides, etc.), as well as carbon materials such as CNTs and carbon cloth, seems to be a very promising strategy to realize flexible enough electrode materials for the development of wearable devices, self-charged energy storage devices and microsupercapacitors. In all cases, multi-metallic sulfide-based core@shell materials play a key role as electroactive materials for realization of high performance, portable and flexible energy storage devices paving the way to a more advanced and sustainable society.