Search results for "Pellet"

Direct determination by portable ED-XRF of mineral profile in cocoa powder samples

2019

Abstract The present study has exploited the rapidity of the analysis and the multi-elemental capability of the energy dispersive X- ray fluorescence (ED-XRF) technique for the mineral profile determination in cocoa powder. A fast, cheap and environmental sustainable method without reagent consumption or toxic waste generation has been proposed. The samples can be prepared in the form of pellets of 13 mm in diameter and 2–3 mm thickness. The different internal calibrations used by ED-XRF equipment did not provide accurate results when comparing the mineral profile with the concentration obtained by Inductively Couple Plasma Optical Emission Spectroscopy (ICP-OES) after microwave assisted di…

Properties of spark plasma sintered nanostructured Zn1+xSb

2011

Engineering materials with specific physical properties has recently focused on the effect of nanoscopic inhomogeneities at the 10 nm scale. Such features are expected to scatter medium and long-wavelength phonons lowering thereby the thermal conductivity of the system without simultaneously decreasing the charge transport (phonon–glass electron–crystal concept). A new Zn1+xSb nanophase obtained by a wet chemical approach was densified by spark plasma sintering (SPS). Investigations on compounds subsumed as “Zn4Sb3” always suffer from its low thermal stability and the contamination of the nanoparticles with solvents and additives used in the synthesis. In order to gain insight into this com…

Semi-continuous feeding and gasification of alfalfa and wheat straw pellets in a lab-scale fluidized bed reactor

2015

Abstract Small scale air-blown fluidized bed gasification of alfalfa and wheat straw pellets were conducted for semi-continuous solid feeding and range of operating conditions varied due to the modifications in equivalence ratio (ER) (0.20–0.35) achieved both by varying solid and air input. Alfalfa pellets displayed an improvement in several gasification variables such as gas lower heating value (∼4.1 MJ/Nm3), specific gas yield (1.66 Nm3/kg), cold gas efficiency (∼42%) and carbon conversion efficiency (∼72%) as ER maximized to 0.35 which was found optimum for this feedstock for the present course of experiments. Gasification parameters of wheat straw pellets on the other hand were characte…

Influence of electric field on thermo-chemical conversion of mixtures of straw pellets with coal

2018

Considerations on factors affecting biochar densification behavior based on a multiparameter model

2021

The optimization of upscaled biochar pelleting is limited by lack of knowledge regarding the effects of process parameters. A multiparameter model, coupled to a single pellet press unit, was for the first time applied to biochar production to predict the upscaled biochar pelleting process behavior. The model permits to estimate in a time and cost-effective way how the die friction forces, quantified through the pellet exiting pressure, are affected by the key process parameters. It was observed that to achieve acceptably low exiting pressures (in the order of 100 MPa), it was critical to produce biochar at high temperatures (e.g. 600 °C). Addition of water as a binder is also beneficial, wh…

X-ray micro-computed tomography investigation of fibre length degradation during the processing steps of short-fibre composites

2014

The mechanical properties of composites in the fibre direction are mainly attributed to the fibre slenderness, or aspect ratio. A trade-off between performance and processability is usually required, and dependent on the intended application. If the fibre length could be retained or not severely degraded during various processing steps towards the injection-moulded component, a stiffer and stronger composite product could be obtained. The processing steps for injection moulded wood-fibre composites here include: Pulping, commingling, extrusion, pelletizing, and injection moulding. To tune the processing parameters systematically for retained fibre length, it would be useful to investigate t…

Ultralow thermal conductivity in 1D and 2D imidazolium-based lead halide perovskites

2021

Low-dimensional hybrid organic–inorganic metal halide perovskites are rapidly emerging as a fascinating sub-class of the three-dimensional parent structures, thanks to their appealing charge and thermal transport properties, paired to better chemical and thermal stabilities. Extensive investigations of the thermal behavior in these systems are of paramount relevance to understand their optoelectronic and thermoelectric applications. Herein, we present a complete thermophysical characterization of imidazolium lead iodide, (IMI)PbI3, a 1D pseudo-perovskite with chains of face-sharing octahedra, and histammonium lead iodide, (HIST)PbI4, a 2D layered perovskite with corner-sharing octahedra. Up…

Actinomadura pelletieri mycetoma--an atypical case with spine and abdominal wall involvement.

2011

We describe a case of mycetoma caused by Actinomadura pelletieri with simultaneous involvement of the spine, abdominal wall and retroperitoneal space in a man who had suffered from ‘Madura foot’ 10 years earlier. The characteristics of this case were analysed and contextualized among those of other cases of mycetoma caused by other micro-organisms found through a review of the international literature. The rarity of the disease in industrialized countries and its possible atypical presentations may hinder a prompt diagnosis. Culture techniques that allow detection of slow-growing fungi and actinomycetes should be routinely used when dealing with tissue samples from patients from tropical an…

Mechanical and barrier properties of extruded film made from sodium and calcium caseinates

2014

Abstract Over the past few years, much interest has been placed into the investigation of increased barrier and mechanical properties of protein films via a multitude of approaches. Generally, these techniques involve modifications of interactions among protein molecules, such as ionic crosslinking using divalent ions. To evaluate the crosslinking effect of Ca 2+ cations, films were made from calcium caseinate (CaCAS) and/or sodium caseinate (NaCAS). The production of caseinate thin films was carried out in two steps: first thermoplastic pellets were made using a co-rotating twin-screw extruder, then they were transformed into thin films (60 μm) using a classical film blowing machine. Tensi…

The Influence of The Degree of Grinding to Obtain of Some Fermented Mashes Based on Whole Wheat and Husked Millet

2011

The purpose of this article was to study the influence of degree of milling whole wheat (was ground in 4 variants of grain) and husked millet (was finely ground) to obtain fermented mashes type Braga. There have been 4 mashes of grist of whole wheat, grist husked millet, hop pellets and water and were boiled under continuous stirring and then cooled. Their content has diluted with water and then strainer by pressed through a sieve. Each mash-filtrate has divided in two and added white sugar 7%, resulting two series of sweet mashes. One has inoculated with a mixed culture of yeast and lactic bacteria and the other only with yeast culture. After fermentation were analyzed fermented mashes (pH…