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In this work, ceramic shell foams produced by direct foaming and gelcasting of proteins containing 35 vol.% of solids were efficiently tailored through the optimization of suspension parameters, foaming and also according to the gelling temperature. These were key parameters employed for controlling the foamability and foam stability, and hence the foam porosity and pore characteristics after the sintering process. The potential of using microtomography in characterizing the morphometric parameters of foams was explored. Airflow permeability measurements (∼24 °C to 727 °C) were performed in order to investigate the applicability of such materials in the fluid flow field. The samples exhibited a wide range of pore sizes (60 ± 5–1700 ± 90 μm), porosity values higher than 80 %, Darcian (k1) and non-Darcian (k2) permeability coefficients values in the ranges of 1.32–1.83 x 10−9 m2 and 8.34–22.46 x 10-5 m, respectively.

Computational analysis applicability to paleontological images ranges from the study of the evolution of animals, plants and microorganisms to the habitat simulation of living beings from a specific epoch. It can also be applied in several niches, e.g. oil exploration, where several factors can be analyzed in order to minimize costs related to oil extraction. One specific factor is the characterization of the environment to be explored. This analysis can occur in several ways: use of probes, samples extraction, correlation with logs of other drilling wells and so on. During the samples extraction phase, the Computed Tomography (CT) is of extreme importance, since it preserves the sample and makes it available for several analyses. Based on 3D images generated by CT, analyses and simulations can be performed, and processes currently performed manually and exhaustively, can be automated. In this work, we propose and validate a method for fully automated microfossil identification and segmentation. A pipeline is proposed that begins with scanning and ends with the microfossil segmentation process. For the microfossil segmentation, a Deep Learning approach was developed, which resulted in a high rate of correct microfossil segmentation (98% IOU). The validation was performed both through an automated quantitative analysis and visual inspection. The study was performed on a limited dataset, but the results provide evidence that our approach has potential to be generalized to other carbonatic rock substrates. To the extent of the authors' knowledge, this paper presents the first fully annotated MicroCT acquired microfossils dataset made publicly available.

The Earth, Moon and Mars samples have been investigated in terms of gamma ray energy absorption buildup factors ( EABF ) depending on penetration depth, weight fraction of constituent elements and photon energy. The five parameter geometric progression (G-P) fitting approximation has been used to compute the buildup factors in the energy region 0.015–15 MeV up to a penetration depth of 40 mean free paths (mfp). The maximum values of EABF have been observed for the Earth, Mars and Moon samples at 0.2, 0.3 and 0.2 MeV, respectively. At the corresponding energies where maximum EABF occur, the Earth samples have the highest and the Mars samples have the lowest EABF values. There is no significant variation in EABF for the Earth, Moon and Mars samples beyond 1 MeV, hence the values of EABF remain constant with the variation in chemical composition for all the given materials. Finally, the buildup factors so obtained have been discussed in function of the penetration depth, weight fraction of constituent elements and photon energy.

Samples of concrete for popular habitation (0.1×0.03×0.1 m) and cellular concrete (0.1×0.05×0.1 m) were submitted to water vertical ascending infiltration. The moisture content spatial and temporal evolution of each sample it was monitored in three halfway positions in a same horizontal line, applying the gamma rays transmission method. The data were taken with a 137Cs (3.7×1010 Bq, 0662 MeV) source, Nal (Tl) of 2×2″ detector coupled to gamma ray spectrometry standard electronic with multichannel analyzer and a micrometric table. For the popular habitation concrete, there was a clear correlation between wetting profiles and concrete strength. The cellular concrete showed a wetting profile compatible to its greater porosity.