Investigation of Ga Doping for Non-stoichiometric Sodium Bismuth Titanate Ceramics

Abstract

The electrical performance of Ga3+ doping Na0.5Bi0.5TiO3-based oxygen ion conductor was studied. The Na0.52Bi0.47Ti1−xGaxO3−δ (x = 0, 0.01, 0.015, 0.02) samples were fabricated by the means of traditional solid-state reaction. The results of AC impedance measurement show that the bulk conductivity of Na0.52Bi0.47Ti1−xGaxO3−δ samples decrease monotonously with the increase of Ga3+ doping. At 673 K, the bulk conductivity of the Na0.52Bi0.47Ti0.98Ga0.02O3−δ sample is 7.19×10− 4 S/cm, which is lower than that of Na0.52Bi0.47TiO3−δ sample under the identical test temperature. The highest total conductivity emerges in the Na0.52Bi0.47Ti0.99Ga0.01O3−δ sample with 1.387×10− 4 S/cm at 623 K for the Ga3+ doping content of 1 mol%, which demonstrate that a slight of Ga3+ doping supports the enhancement of the total conductivity. A relaxation peak was observed in the Na0.52Bi0.47Ti1−xGaxO3−δ compounds. As the Ga3+ ions were introduced into the Na0.52Bi0.47TiO3−δ compound, there is an increasing trend of the relaxation activation energy educed by the internal friction test. In addition, the oxygen relaxtion height of Na0.52Bi0.47Ti1−xGaxO3−δ samples decreases along with the introduction of the Ga3+ doping, suggesting that the introduction of the Ga3+ leads to the decrease of mobile oxygen vacancy .

hsa_circ_0131457 regulates SFRP2 through miR-636 to inhibit the invasion and metastasis of pancreatic cancer

“…Overexpression of hsa_circ_0000662 and has_circ_0086375 inhibits the proliferation and invasion of pancreatic cancer cells, induces cell apoptosis, and thereby inhibits tumor growth [9][10]. The up-regulated expression level of hsa_circ_0006988 in pancreatic cancer tissues and plasma is associated with clinical stage, lymph node invasion, and distant metastasis, making it a potential molecular marker for prognosis evaluation [11]. Additionally, certain combinations of cirRNA signals have shown potential in improving the sensitivity and specificity of early pancreatic cancer diagnosis, as well as improving prognosis and quality of life.…”