In this research, a screw-barrel system was designed and implemented, coupled with material extrusion, to print high-melt-temperature thermoplastic materials. The aim was to integrate two methods: the direct extrusion of thermoplastic polymer pellets with material extrusion,utilize various polymers in the form of pellets, especially high melt temperature ones, instead of traditional filaments. This addresses one of the significant challenges in filament preparation for various materials that are not readily available in the market or nearly impossible to fabricate (such as highly filled plastics). First, the screw-barrel assembly performance and factors influencing feed rate were evaluated. Subsequently, specimens were printed with polyether ether ketone (PEEK), an advanced plastic material known for its outstanding mechanical properties, high-temperature tolerance, and broad applications in various sectors, such as medical. Additionally, the material was reinforced with 2.5% continuous glass fibers while printing, which presented a novel product. Upon comparing theoretical values with experimental data from the tensile testing, a notable observation emerged: the inclusion of 2.5% glass fibers led to an approximate 43% increase in the tensile strength of the material. Furthermore, SEM images provided visual evidence of satisfactory adhesion between layers and fibers.

The present work presents and discusses an analysis of the floor types of Villa of Diomedes (Pompeii archaeological park in the Campania region, Italy) both from architectural, archaeological, and structural point of view. In particular, the geometrical structural parameters of different floor types and the rules used by ancient builders to design them are investigated by means of interdisciplinary research. Link between structural-based assumptions, archival sources, geometric survey, in situ visual inspections and the archaeological information make it possible to define the geometrical structural parameters of eleven-barrel vaults, three wooden floors and three sloped wooden roofs (buried and collapsed during the Vesuvius eruption). A specific study of the barrel vaults is presented to investigate the relationships between the main vaults’ structural parameter. Furthermore, a comparison between the vaults’ dimensions obtained from surveys and those produced by the literature formulations from the 15th to the 20th centuries concerning masonry-vault designs is presented and discussed. These analyses carried out in the framework of Villa of Diomedes interdisciplinary project was very useful to interpret the fabrication of the Villa and to make a reconstruction of 3D model as it probably resulted to be the fateful year of 79 A.D.

The available magnetic field strength for high resolution NMR in persistent superconducting magnets has recently improved from 23.5 to 28 Tesla, increasing the proton resonance frequency from 1 to 1.2 GHz. For magic-angle spinning (MAS) NMR, this is expected to improve resolution, provided the sample preparation results in homogeneous broadening. We compare two-dimensional (2D) proton detected MAS NMR spectra of four membrane proteins at 950 and 1.2 GHz. We find a consistent improvement in resolution that scales superlinearly with the increase in magnetic field for three of the four examples. In 3D and 4D spectra, which are now routinely acquired, this improvement indicates the ability to resolve at least 2 and 2.5 times as many signals, respectively.