Electrical conduction and oxygen diffusion mobility in the bixbyite ( Ia3̅) and rhombohedral ( R3̅) polymorphs of the LnMoO (Ln = Er, Tm, Yb; Δ = δ, δ1, δ2; δ1 > δ2) heavy lanthanide molybdates, belonging to new, previously unexplored classes of potential mixed (ionic-electronic) conductors, have been studied in the range of 200-900 °C. The oxygen self-diffusion coefficient in bixbyite ( Ia3̅) YbMoO phase estimated by the temperature-programmed heteroexchange with CO was shown to be much higher than that for rhombohedral ( R3̅) RI (with large oxygen deficiency) and ( R3̅) RII (with small oxygen deficiency) LnMoO (Ln = Tm, Yb; Δ = δ1; δ1 > δ2) oxides. According to the activation energy for total conduction in ambient air, 0.99, 0.93, and 1.01 eV in ErMoO, TmMoO and YbMoO bixbyites, respectively, oxygen ion conductivity prevails in the range ∼200-500 °C. Oxygen mobility data for the rhombohedral LnMoO (Ln = Er, Tm, Yb; Δ = δ1, δ2) phases RI and RII indicate that the oxygen in these phases exhibits mobility at much higher temperatures, such as those above 600-700 °C. Accordingly, below 600-700 °C they have predominantly electronic conductivity. As shown by total conductivity study of LnMoO (Ln = Er, Tm, Yb) bixbyites ( Ia3̅) and rhombohedral phases LnMoO (Ln = Er, Tm, Yb; Δ = δ1, δ2) ( R3̅) in dry and wet air, the proton conductivity contribution exists only in LnMoO (Ln = Er, Tm, Yb) bixbyites up to 450-600 °C and decreases with a decreasing of the lanthanide ionic radius. The obtained data on the mobility of oxygen and the presence of proton contribution in bixbyites in the 300-600 °C temperature range make it possible to confirm unequivocally that LnMoO (Ln = Er, Tm, Yb) bixbyites are mixed electron-proton conductors at these temperatures.
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http://dx.doi.org/10.1021/acs.inorgchem.8b03397 | DOI Listing |
J Eur Acad Dermatol Venereol
October 2024
Clifton Insight, Bristol, UK.
Vet Anim Sci
September 2024
Food Science Division: Microbial Biochemical and Food Biotechnology, Faculty of Natural and Agricultural Sciences, PO Box 339, Bloemfontein, 9300, South Africa.
The effects of A (African wormwood) essential oil incorporation in diets on meat quality and fatty acid profilers of broilers was assessed. Four hundred Cobb500 day-old chicks were obtained and placed randomly into the following 4 diets replicated 10 times: NC-Negative control (broiler diet without antibiotics), PC-positive control (broiler diet with zinc bacitracin), AA1-broiler diet + 0.1 % essential oil and AA2 - broiler diet + 0.
View Article and Find Full Text PDFAdv Mater
October 2024
State Key Laboratory of Polymer Physics and Chemistry, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China.
Dipole moment arrangement in organic semiconductors plays a critical role in affecting the intermolecular packing, determining optoelectronic properties and device performance. Here, to get the desired fill factor (FF) values in organic solar cells (OSCs), the local dipole of non-fullerene acceptors (NFAs) is modulated by changing the molecular asymmetries. Two NFAs, AA-1 and AA-2 are designed and synthesized, which have different substitutions of alkyl and alkoxyl groups.
View Article and Find Full Text PDFJ Agric Food Chem
July 2024
State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Provincial Key Laboratory of Pharmaceutics, Guizhou Medical University, Guiyang, Guizhou 550004, PR China.
Dermatol Ther (Heidelb)
July 2024
Brigham and Women's Hospital, Boston, MA, USA.
Introduction: Alopecia areata (AA) is an autoimmune disease associated with high rates of emotional and psychosocial distress. The analysis reported here describes the evolution of measures assessing health-related quality of life (HRQoL) and symptoms of anxiety and depression up to week 104 in patients who achieved sustained scalp hair regrowth during treatment with baricitinib in the BRAVE-AA phase III trials.
Methods: This post-hoc analysis included data from the double-blind, parallel-group, randomized, placebo-controlled phase III trials BRAVE-AA1 (ClinicalTrials.
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