72 documents found, page 1 of 8

Future gamma-ray missions’ polarimetric prospects

Orbit-Like Proton Radiation Sensitivity of CdTe Detectors: Evaluation of Mobili...

Metal contaminants in cinnamon samples marketed in Portugal

"Cinnamon has long been used by man for medicinal purposes and as a spice in many traditions wordwhile. Regardless of its alleged healing properties, spices and herbs may be the source of undesirable toxic elements. The presence of metals such as Al, Hg, Cd, Pb, Mn, among others, in food and food supplements, even at restricted values, may cause deleterious effects to human health. Although the consumption of c...

A study on fiber sedimentation velocity in epoxy/steel fiber composites used fo...

Composites based on metallic fibers and thermosetting polymers are being increasingly used for molding blocks of hybrid injection molds, thereby improving the mechanical and thermal properties. However, an adequate study on the behavior of steel fibers in a reactive epoxy resin is necessary to understand how to maintain suitable mold properties. In this paper, the sedimentation velocity of short steel fiber sus...

In-line particle size assessment of polymer suspensions during processing

The validation and the operating window of an in-line rheo-optical slit die coupled to a prototype single/twin-screw mini-extrusion system are reported. This experimental set-up is able to perform in-situ rheological measurements, together with Small Angle Light Scattering (SALS) and Polarized Optical Microscopy (POM), thus enabling the structural characterization of materials during extrusion. The optical vali...

Assessing the practical utility of the hole-pressure method for the in-line rhe...

The most promising method capable of providing accurate measurements of the first and second normal-stress differences in shear flows at shear rates typical of polymer processing is the so-called hole-pressure method, but its use has not been as widespread as would be expected, namely due to the experimental difficulties associated with performing such experiments accurately. In this work, we use a small-scale ...

In-line optical characterization during extrusion of polymer blends

The assessment of morphological development during the extrusion of small amounts of high-valued polymer-based systems is critical for understanding the processability of new plastics and for monitoring the extrusion of complex formulations. However, reports on the structural development during the extrusion of industrial plastics, measured by means of in-line optical techniques, are still scarce. In this contr...

In-line rheo-optical characterisation of polymeric systems

As increasingly more sophisticated polymer systems are being developed, it is important to rapidly estimate their processability, morphology after processing and performance under service conditions, if possible using small amounts of materials. In order to accomplish this, a single I twin-screw mini-extrusion system of modular construction, with well-controlled outputs in the range 30-300 g/h, was coupled to a...

Effect of guar gum on the physicochemical, thermal, rheological and textural pr...

In attempts to produce a low-fat cheese with a rheology and texture similar to that of a full-fat cheese, guar gum (within 0.0025–0.01%; w/v, final concentration) was added to low-fat milk. The obtained cheeses were characterised regarding their physicochemical, thermal, rheological and textural properties. Control cheeses were also produced with low and full-fat milk. The physicochemical properties of the guar...

In-line rheo-optical characterization in gram scale extrusion of materials

Extruders are a fundamental part of any extrusion or compounding line. Single-screw extruders are of general-purpose application, while intermeshing twin-screw machines have found special application niches, mainly because of their good mixing capabilities. When only small quantities of (expensive or experimental) materials are available, it is often necessary to extrude at small, laboratorial scales. In additi...