Role of Potassium and Calcium on the Combustion Characteristics of Biomass Obtained from Thermogravimetric Experiments

This work focuses on the combustion behavior of raw and demineralized grape pomace and grape pomace doped with 0.1, 0.5, 0.82 (equal to the K concentration in the raw biomass), 3, and 6 wt % K and 0.1, 0.5, 1.08 (equal to the Ca concentration in the raw biomass), 3, and 6 wt % Ca. To identify the individual role of calcium and potassium, the biomass samples were either pyrolyzed in a N₂ atmosphere or oxidized in air in a thermogravimetric analyzer (TGA) during non-isothermal runs at 10 K/min from room temperature to a maximum temperature of 1275 K. In all of the cases, the biomass pyrolysis process shows one main stage associated with the volatile matter release. This process is not significantly affected by the mineral content of biomass nor the presence of high K and Ca contents. During combustion in air, the biomass samples show two main distinct stages that are associated with the volatile matter release and the char oxidation. Whereas the main devolatilization stage is not significantly affected by the mineral content of the biomass, the char oxidation stage is shifted to higher temperatures for the demineralized biomass. Potassium and calcium play a different role on the char oxidation process. In general, char oxidation is promoted with increasing the K content, whereas Ca does not significantly influences this process. The TGA results were also used to determine the kinetic parameters of the pyrolysis and combustion processes of biomass in the presence of K and Ca

Morphological, yield, cytological and molecular characterization of a bread wheat x tritordeum F hybrid

Morphological, yield, cytological and molecular characterization of a bread wheat x tritordeum F hybri

DS_10.1177_0022034518765762 – Supplemental material for Micropatterned Silica Films with Nanohydroxyapatite for Y-TZP Implants

<p>Supplemental material, DS_10.1177_0022034518765762 for Micropatterned Silica Films with Nanohydroxyapatite for Y-TZP Implants by R.B.P. Miranda, L. Grenho, A. Carvalho, M.H. Fernandes, F.J. Monteiro, and P.F. Cesar in Journal of Dental Research</p

Creating a Stable Oxide at the Surface of Black Phosphorus

The stability of the surface of in situ cleaved black phosphorus crystals upon exposure to atmosphere is investigated with synchrotron-based photoelectron spectroscopy. After 2 days atmosphere exposure a stable subnanometer layer of primarily P₂O₅ forms at the surface. The work function increases by 0.1 eV from 3.9 eV for as-cleaved black phosphorus to 4.0 eV after formation of the 0.4 nm thick oxide, with phosphorus core levels shifting by <0.1 eV. The results indicate minimal charge transfer, suggesting that the oxide layer is suitable for passivation or as an interface layer for further dielectric deposition