Iron oxidation state effect on the Mg-Al- Si-O glassy system

Mg-Al-Si-O glassy systems have a great importance in a wide range of industrial applications, specifically as an electrolyte for molten oxide electrolysis processes in steelmaking. Understanding how the iron oxidation state of the raw material (Fe2+/Fe3+) and its corresponding amount influence this glassy system's properties will be the aim of the current work. Iron oxides (as Fe2O3 or Fe3O4) were used to dope Mg-Al-Si-O system obtaining amorphous materials through an unconventional method: Laser Floating Zone (LFZ). Above 8% mol of Fe formation of magnetic phases or iron clusters, were observed in the glass matrix. Samples with Fe2O3 showed a higher crystal concentration, when compared with Fe3O4. The electron paramagnetic resonance measurements show a strong dependence on the iron source (Fe3O4 or Fe2O3). In addition, the magnetization decreases linearly with iron content, independently of iron oxidation state, except for samples with a higher concentration of Fe2O3(15% mol), due to sample crystallization. Moreover, with Fe3O4 as raw material there is an improvement (~250 times) of the electrical conductivity when compared with Fe2O3. The results show that the presence of Fe2+ on the glass influences the electrical conductivity, which could have impact in the efficiency of molten oxide electrolysis process.publishe

Cardiopoietic cell therapy for advanced ischemic heart failure: results at 39 weeks of the prospective, randomized, double blind, sham-controlled CHART-1 clinical trial

Cardiopoietic cells, produced through cardiogenic conditioning of patients' mesenchymal stem cells, have shown preliminary efficacy. The Congestive Heart Failure Cardiopoietic Regenerative Therapy (CHART-1) trial aimed to validate cardiopoiesis-based biotherapy in a larger heart failure cohort

PLAGIOCLASE COMPOSITION ON THE VITOSHA PLUTON (BULGARIA) BY X-RAY MAPS

Electron microscopy X-ray elemental analysis is used to characterize the plagioclase composition of the Vitosha pluton. The Vitosha pluton crops out in the western part of the Srednogorie structural zone. The plutonic body is composed of abyssal gabbros and anorthosites, hypoabyssal monzonites, syenites and late veins of granosyenitic composition. The major rock-forming mineral phases are plagioclase, K-feldspar, amphibole and clinopyroxene. Common accessory minerals include apatite, titanite, magnetite, ilmenite and zircon. Secondary minerals are epidote, tourmaline, chlorite, actinolite, adularia and clay minerals. Plagioclase crystals characterized by compositional zoning are typical of the Vitosha pluton

New fired bricks based on municipal solid waste incinerator bottom ash

The main objective of this work was to study the sintering process and technological properties of new fired bricks based on high amount of post-treated municipal solid waste incinerator bottom ash and refractory clay. In addition, the effect of the minor addition of flux (Na2CO3) or reinforce (corundum) was also highlighted. Several methods were used to study the effect of compositions variations on the sintering process, structure and the mechanical characteristics of the test briquettes. Differential thermal analysis (TG/DTA) and dilatometry techniques were applied to study the thermal behaviour while scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy and high-temperature X-ray diffraction were used to elucidate the structure and the phase composition. The mechanical characteristics were estimated by micro-indentation, strength and various physical tests (porosity, linear shrinkage and water absorption, etc). The results highlight the possibility to use very high amount of municipal solid waste incinerator bottom ashes in the production of new fired bricks with good performances at all levels. It is also shown that the addition of additives managed the final properties, affecting the crystal phase formation, porosity and greatly the strength of the samples

Serum and Urine Copper – Contamination and Stability

Pre-analytical factors of variation need to be carefully considered and investigated in efforts to harmonize all aspects of the total testing process. This study aimed to evaluate contamination and stability in copper (Cu) analysis of serum and urine by flame atomic absorption spectroscopy (FAAS) and to compare the stability of urine Cu in controls and in D-penicillamine (D-PA) administration. Cu was measured by AAnalyst 400, Perkin Elmer, USA. Blood was collected in BD Vacutainer®SSTTM II Advance tubes and BD Vacutainer® Trace Element tubes. Sterile polyethylene and polypropylene vessels for collection, transportation, storage and preliminary preparation of samples were used in urinalysis. Stability in serum and 24 h urine was evaluated in two temperature regimens: 15-25°C and 2-8°C, for particular time of storage. No significant differences (p = 0.20) in Cu concentration was found between the two types of tested tubes with patient`s sera. The stability of the samples (serum and urine) was better at refrigeration temperature. In urine the stability was better in D-PA administration.Standardization of Cu analysis could be achieved by assessing the aspects of pre-analytical factors of variations

New ceramic materials from MSWI bottom ash obtained by an innovative microwave-assisted sintering process

Preliminary results on the production of new ceramic bricks by an innovative microwave-assisted sintering process employing MSWI bottom ashes are reported. Microwave heating technique was compared with a conventional thermal treatment with the aims to: (1) study the influence of heat treatment method on the crystallization behavior and on the microstructure of obtained samples; (2) define the crystallization evolution in microwave field; (3) gain an insight into the physical properties of the new samples. Higher crystallinity and new crystal phases were observed in the samples prepared by microwave heating, where precipitation of new sodium rich crystal phases was observed, together with quartz and anorthite, formed in the conventionally prepared samples. The possibility to obtain novel bricks with huge waste amount, in a very short thermal cycle and at relatively low temperatures was demonstrated with significant reductions in the energy demand for their production. Finally, the samples obtained by microwave-assisted sintering are characterized by improved mechanical properties