RESUMO
Polymer/layered silicate composites have gained huge attention in terms of research and industrial applications. Traditional nanocomposites contain particles regularly dispersed in a polymer matrix. In this work, a strategy for the formation of a composite thin film on the surface of a polycaprolactone (PCL) matrix was developed. In addition to the polymer, the composite layer was composed of the particles of saponite (Sap) modified with alkylammonium cations and functionalized with methylene blue. The connection between the phases of modified Sap and polymer was achieved by fusing the chains of molten polymer into the Sap film. The thickness of the film of several µm was confirmed using electron microscopy and X-ray tomography. Surfaces of precursors and composite materials were analyzed in terms of structure, composition, and surface properties. The penetration of polymer chains into the silicate, thus joining the phases, was confirmed by chemometric analysis of spectral data and changes in some properties upon PCL melting. Ultimately, this study was devoted to the spectral properties and photoactivity of methylene blue present in the ternary composite films. The results provide directions for future research aimed at the development of composite materials with photosensitizing, photodisinfection, and antimicrobial surfaces.
Assuntos
Azul de Metileno , Polímeros , Poliésteres/química , Polímeros/química , Silicatos/químicaRESUMO
The data presented in this paper are related to the research article "Sub-bottom and bathymetry sonar inspection of postglacial lacustrine infill of the alpine lakes (Tatra Mts., Slovakia)" (Dhavamani et al., 2022). An implementation of acoustic sonar protocols provided data for the interpretation of glacigene, glaciolacustrine, postglacial, mass-movement deposits, and geodynamic factors influencing the sedimentation in seven alpine and sub-alpine Tatra Mountains lakes. The field data document the survey track lines of the sonars and allow to identify the location of the geomorphologic phenomena described in (Dhavamani et al., 2022). The laboratory data obtained by micro-CT document the lithology of glaciolacustrine and postglacial lake infill and support the interpretation of sub-bottom sonar record.
RESUMO
A marked 120 My gap in the fossil record of vampire squids separates the only extant species (Vampyroteuthis infernalis) from its Early Cretaceous, morphologically-similar ancestors. While the extant species possesses unique physiological adaptations to bathyal environments with low oxygen concentrations, Mesozoic vampyromorphs inhabited epicontinental shelves. However, the timing of their retreat towards bathyal and oxygen-depleted habitats is poorly documented. Here, we document a first record of a post-Mesozoic vampire squid from the Oligocene of the Central Paratethys represented by a vampyromorph gladius. We assign Necroteuthis hungarica to the family Vampyroteuthidae that links Mesozoic loligosepiids with Recent Vampyroteuthis. Micropalaeontological, palaeoecological, and geochemical analyses demonstrate that Necroteuthis hungarica inhabited bathyal environments with bottom-water anoxia and high primary productivity in salinity-stratified Central Paratethys basins. Vampire squids were thus adapted to bathyal, oxygen-depleted habitats at least since the Oligocene. We suggest that the Cretaceous and the early Cenozoic OMZs triggered their deep-sea specialization.