Perovskite oxyhydrides may find diverse applications, ranging from catalysis, topochemical synthesis to solid state ionics, but the understanding of their hydride transport behavior has remained limited. Here, gaseous hydrogen exchange and release experiments were analyzed using the Kissinger method to estimate the activation energy (E a) for H/D exchange and H2 release in BaTiO3–x H x (x = 0.35–0.60) and LaSrCoO3H0.70. It is revealed that, for each BaTiO3–x H x at a given hydride concentration (x), both H/D exchange and H2 release experiments provide similar E a values. For BaTiO3–x H x with different x, the obtained E a values significantly decrease with increasing x until around 0.4; beyond 0.4, it becomes nearly constant (200–220 kJ mol–1). This observation suggests that the diffusion process in the low hydride concentration (x < 0.4) includes oxide as well as hydride diffusion, whereas, for 0.4 < x (<0.75), only hydride migrates, with second-nearest-neighbor (2NN) jumps as a rate-determining process, which is supported by DFT calculations. The Kissinger analysis of LaSrCoO3H0.70 yielded a similar E a of 170–190 kJ mol–1, consistent with the 2NN hopping scenario. The presented method provides a facile tool for designing and improving hydride conductivity in oxyhydrides regardless of the presence of electronic conductivity.
Correlated motion dynamics of electron channels and domain walls in a ferroelectric-gate thin-film transistor consisting of a ZnO/Pb(Zr,Ti)O3 stacked structure J. Appl. Phys. 110, 084106 (2011); 10.1063/1.3651098 V 5 + ionic displacement induced ferroelectric behavior in V-doped ZnO films Appl. Phys. Lett. 90, 242903 (2007); 10.1063/1.2748081Off-centered polarization and ferroelectric phase transition in Li-doped ZnO thin films grown by pulsed-laser ablation
We examined the role of the large intestine in zinc absorption in rats in three separate experiments. In the first experiment, we examined apparent zinc absorption in rats fed diets containing graded levels of zinc carbonate (0.015-0.535 mmol Zn/kg diet) and evaluated zinc status on the basis of the zinc concentrations in serum and several tissues. The zinc absorption and the serum zinc concentration increased with the zinc content of the diet up to 0. 153 mmol Zn/kg diet. Femoral and pancreatic zinc levels increased linearly up to 0.229 mmol Zn/kg diet. In the second experiment, a zinc carbonate suspension was administered into the cecum via an implanted cannula or into the stomach via an orogastric tube, and the rats were fed diets with or without a highly fermentable fiber, guar gum hydrolysate (GGH, 50 g/kg diet), with coprophagy prevention. The amount of instilled zinc corresponded to the amount of zinc ingested as a component of the diet by the rats of a control group, 0.229 mmol Zn/kg diet. Apparent absorption of cecally instilled zinc was approximately half that observed when zinc was administered into the stomach in both diet groups. Serum and femur zinc concentrations in the cecum-administered groups were approximately 50 and 25% lower, respectively, than those in rats administered zinc into the stomach. The results demonstrate that, in vivo, the absorptive efficiency in the large intestine is not sufficient to satisfy the rat's zinc requirement and does not change when the luminal environment is substantially altered by feeding GGH. In Experiment 3, the effects of cecocolonectomy on zinc absorption were examined in rats with gastric acid suppression. In the cecocolonectomized groups, serum zinc concentration was lower as a result of treatment with a proton pump inhibitor, omeprazole, than in vehicle-treated rats, but not in sham-operated groups. These findings suggest that the cecum and colon contribute to zinc absorption when absorption in the small intestine is impaired.
A halophyte, the common ice plant (Mesembryanthemum crystallinum L.), shows the maximal growth under salinity, in which almost all crops die. The NaCl-stimulated growth, which is referred to as halophilism, is an important trait for adaptation to salinity, but the mechanism is still unclear. To elucidate factors contributing to the halophilism, we tested the effects of NaCl on growth, ion accumulation, and expression of ion homeostasis-related genes in suspension-cultured cells. Among nine ions analyzed, Na + , Cl − , K + , and NO 3 − were accumulated significantly in the cells showing halophilism than that in the salt-untreated cells, and the accumulation of these ions was positively correlated with the growth. Also, the expression of ion homeostasis-related genes for plasma membrane transporters and channels for incorporation of nitrate (McNRT1), sodium (McHKT1), potassium (McKmt1), cations/Cl − (McCCC1), for tonoplast antiporters H + /Cl − (McCLC1) and Na + /H + (McNHX1), and V-ATPase subunit c (McVmac1) for sequestration of Cl − and Na + into the vacuole, and for enzymes catalyzing biosynthesis of proline (McP5CS) and ononitol (McImt1) was higher in the cells showing halophilism than that in the salt-untreated cells. These results indicate that the ion accumulation and the expression of ion homeostasis-related genes contribute to the NaCl-stimulated growth enhancement in the halophyte, the common ice plant. Abbreviations: CCC: cation/Cl-cotransporter; CLC: H+/Cl-antiporter; DW: dry weight; FW: fresh weight; HAK: high affinity potassium; HKT: high potassium transporter; Imt: myo-inositol O-methyl transferase; MIP: major intrinsic protein; NHX: Sodium/proton antiporter; P5CS: delta 1-pyrroline-5-carboxylate synthase; PCV: Packed cell volume; PEG: polyethylene glycol; XTH: xyloglucan endotransglucosylase/ hydrolase The growth enhancement of the ice plants by NaCl was positively correlated with K + accumulation and the increased expression of ion homeostasis related genes contribute to the halophilism. 0 mM 100 mM ARTICLE HISTORY
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.