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This study examines the carbonaceous aerosols emitted from an indoor wood stove operating with two common oaks characterized by well distinct moisture contents (%). The results presented in this work indicate that all emission factors are significantly influenced by the amount of moisture contents. In particular, with wood samples characterized by 10.34% and 56.31% moisture contents, the total carbon emission factors per wood unit were 0.25 ± 0.05 g/kg and 1.12 ± 0.09 g/kg, respectively. In addition, the PM10 emission factors of wood characterized by a low-moisture content were quite low compared with the PM10 recognized from wood with high-moisture contents. The emission factors of woods with low-moisture contents and high-moisture contents were in the lower and higher end, respectively, of the concentration ranges reported in the literature. The main results presented in this experimental article improve some recent results reported in the literature.

Barium-chromium oxide (BaCrOx) coated Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) tubular membranes were successfully prepared and evaluated for oxygen separation applications under high pressure–temperature conditions. The oxygen permeation flux was measured in accordance with the temperature, air pressure, and retentate flow rate, ranging from 750–950°C, 3–9 atm, and 200–1000 mL/min, respectively. The permeation testing on the BaCrOx coated BSCF tubular membranes showed that the oxygen flux increased as the temperature, pressure, and retentate flow rate increased. The oxygen permeation flux was 5.7 mL/(min cm2) with temperature, pressure, and retentate flow rate of 900°C, 9 atm, and 1000 mL/min, respectively. The temperature dependence of the oxygen permeation process is further investigated, and the Arrhenius pre-exponential factor, as well as the apparent activation energy, is determined.

For any potential reader, the front cover of Early Responses to the Periodic System, edited by Masanori Kaji, Helge Kragh, and Gabor Pallo, looks intriguing. The cover image is taken from a paintin...

In the present study, La0.7Sr0.3Co0.5Fe0.5O3-δ powders have been prepared by thermal decomposition of amorphous citrate precursors by calcination at high temperature. The material properties are characterized by thermogravimetric-differential thermal analysis, X-ray diffraction, and four probe method. A perovskite structure with rhombohedral symmetry has been certified for the selected La0.7Sr0.3Co0.5Fe0.5O3-δ oxide membranes. The electrical conductivity of sintered La0.7Sr0.3Co0.5Fe0.5O3-δ ceramics increases with temperature through a maximum, then decreases at relatively higher temperatures, due to oxygen vacancy formation. Oxygen permeation was performed between 700 and 950°C under different oxygen partial pressures (0.21, 0.42, and 0.63 atm) and carbon dioxide concentrations (300, 500, and 700 ppm). According to Arrhenius' law, the oxygen permeation flux of the membranes with a thickness of 1.1 mm increases with temperature and oxygen partial pressure. A maximum oxygen flux of ~0.33 mL/min · cm2 and ~0.25 mL/cm2 · min was measured at 950°C at high oxygen pressure (PO2 = 0.63 atm) and under carbon dioxide concentration range from 300 to 700 ppm, respectively.