Rie Shishido

Comparative Study of Hydrogen- and Deuterium-Induced Degradation of Ferroelectric (Pb,La)(Zr,Ti)O 3 Capacitors Using Time-of-Flight Secondary Ion Measurement

Ferroelectric (Pb,La)(Zr,Ti)O3 (PLZT) capacitors were fabricated with Pt, Al:ZnO (AZO), or Sn:In2O3 (ITO) top electrodes. Hydrogen or deuterium-induced degradation was investigated for the three capacitors by annealing in a 3% H2/balance N2 or 3% D2/balance N2 ambient environment at 200 °C and 1 torr. The remnant polarization of all capacitors decreased after annealing in both H2 and D2 ambient after 45 min, and the remnant polarization of the Pt/PLZT/Pt capacitor significantly decreased after 45-min annealing compared with that of the AZO/PLZT/Pt and ITO/PLZT/Pt capacitors, even though the initial remnant polarization for the Pt/PLZT/Pt capacitor was larger. Time-of-flight secondary ion mass spectrometry showed slight differences in hydrogen content for the three different capacitors after H2 annealing. In contrast, the deuterium content of the Pt/PLZT/Pt and AZO/PLZT/Pt or ITO/PLZT/PT capacitors was significantly different after deuterium annealing. Deuterium depth profiles for the Pt/PLZT/Pt capacitor after annealing showed that deuterium conformally exists in the PLZT layer of the Pt/PLZT/Pt capacitor, and deuterium accumulation under the Pt bottom electrode was also observed. This result suggests that diffusion of deuterium in Pt was much higher than that in PLZT. AZO and ITO top electrodes could act as a hydrogen barrier layer for ferroelectric films.

Hydrogen profile measurement of (Pb,La)(Zr,Ti)O 3 capacitor with conductive electrode after hydrogen annealing

We fabricated ferroelectric (Pb,La)(Zr,Ti)O3 (PLZT) capacitors with Pt, Al:ZnO, or Sn:In2O3 top electrodes. The remnant polarization decreased for these PLZT capacitors after forming gas (3%H2/balance N2) annealing at 200°C and 1 Torr, especially for PLZT capacitor with Pt top electrodes due to the catalytic effect of Pt. The time-of-flight secondary ion mass spectrometry depth profile showed that the hydrogen content in PLZT thin films with Pt top electrode increased ca. 2.7 times after forming gas annealing compared with ca. 1.2 times with other electrodes.

Inhalation of Budesonide/Formoterol Increases Diaphragm Muscle Contractility

BACKGROUND Although budesonide/formoterol (BUD/FORM) is used clinically as a steroid/β(2)-agonist single inhaler, it has not yet been clarified whether BUD/FORM has inotropic effects on diaphragm muscles after inhalation. METHODS We examined the effects of BUD/FORM inhalation, endotoxin injection, and BUD/FORM inhalation plus endotoxin injection on diaphragm contractile properties and nitric oxide (NO) production. After these three treatments, the diaphragm muscle was dissected, and its contractile properties were measured. Histochemistry for the reduced form of nicotinamide adenine dinucleotide phosphate diaphorase was performed for each muscle to assess NO production. RESULTS The force-frequency curves showed an upward shift 1 h after inhalation (p < 0.05) in the BUD/FORM inhalation only group. The force-frequency curves showed a downward shift 4 h after injection (p < 0.001) in the endotoxin injection groups. In the BUD/FORM inhalation plus endotoxin injection groups, a downward shift in the force-frequency curves at 4 h after endotoxin injection was prevented. NO production was inhibited in the BUD/FORM inhalation plus endotoxin injection group compared with that of the endotoxin injection only groups. CONCLUSIONS BUD/FORM inhalation has an inotropic effect on diaphragm muscle, protects diaphragm muscle deterioration after endotoxin injection, and inhibits NO production. Increments in muscle contractility with BUD/FORM inhalation are induced through a synergistic effect of an anti-inflammatory agent and β(2)-agonist.

Evaluatioion of deuterium ion profile in (Pb,La)(Zr,Ti)O 3 capacitors structures with conductive oxide top electrode by time of flight secondary ion mass spectrometry

La-doped lead zirconate titanate (Pb,La)(Zr,Ti)O3 (PLZT) films were prepared via chemical solution deposition. Then, Pt, Al-doped ZnO (AZO), or Sn-doped In2O3 (ITO) top electrodes were deposited on the PLZT films to investigate ferroelectric properties. Three kinds of ferroelectric capacitors were annealed in 3% D2 (with N2 as a balance gas) to compare hydrogen-induced degradation of ferroelectric properties. Deuterium ion in ferroelectric capacitor was evaluated by time of flight secondary ion mass spectrometry. For ferroelectric capacitor with Pt top electrode, deuterium ion was detected in PLZT films after 5 min D2 annealing. On the other hands, deuterium ion was slightly detected with AZO and was not detected at all with ITO even after 120 min D2 annealing.

Effects of molecular weight and cationization agent on the sensitivity of Bi cluster secondary ion mass spectrometry: Effects on the sensitivity of Bi cluster SIMS

RATIONALE Bi cluster secondary ion mass spectrometry (SIMS) is one of the most promising tools for precise analysis of synthetic polymers. However, the sensitivity in the high-mass region is still insufficient compared with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS). Accordingly, the effects of metal assistance (cationization agents) were investigated in this study. METHODS To investigate the effects caused by varying the ionization agent, three different polyethylene glycol (PEG) samples were prepared, one with an Ag-deposited film, and two others mixed with Ag and Na, respectively. The measurements were performed by using a commercial Bi cluster SIMS and MALDI-TOFMS systems. The mass spectrum obtained with MALDI-TOFMS was used as a reference molecular weight distribution to evaluate the effects of molecular weight and primary ion species (Bi+ , Bi3+ , Bi32+ ) on the sensitivity of Bi cluster SIMS. RESULTS The intensity of each secondary ion was the highest in Bi32+ irradiation, and the lowest in Bi+ irradiation. Regarding the cationization agents, the secondary ion yield was the highest for the sample mixed with Ag, while the degree of decay of sensitivity along with the increase in molecular weight was the smallest for the sample mixed with Na. CONCLUSIONS It was suggested that the cationization mechanism consists of pre-formed ionization and gas-phase ionization processes. The sensitivity of Bi cluster SIMS decreases to approximately one-fiftieth in every 1000 u. These results might help in understanding the mechanism of cationization and further enhancement of secondary ion yields of polymers. Copyright

Effects of Inhalation or Incubation of Oxitropium Bromide on Diaphragm Muscle Contractility in Mice

BACKGROUND Although oxitropium bromide is used clinically as an anticholinergic drug (i.e., parasympathetic antagonist) to relax airway smooth muscle, we examined whether it has or does not have any effects on diaphragm muscle. METHODS Three treatment sets, an oxitropium bromide inhalation only group, an oxitropium bromide inhalation plus endotoxin injection group (in vivo) and an oxitropium bromide incubation group (in vitro) were studied as to diaphragm muscle contractile properties. RESULTS Oxitropium bromide inhalation shifted force-frequency curves upward at 2 h after inhalation (p < 0.05) and inhibited the decrease of force-frequency curves due to endotoxin injection in vivo. Incubation with oxitropium bromide of untreated diaphragm muscle and diaphragm muscle injected with endotoxin did not increase the force-frequency curves dose-dependently in vitro; however, it caused both types of muscle to be fatigue resistant. CONCLUSIONS We speculate that the increment of muscle contractility with the inhalation of oxitropium bromide was induced by the antagonization of musucarinic acetylcholine receptors (mAChR). In addition, the changes of fatigue resistance provoked by oxitropium bromide, which also is speculated to antagonize mAChR, may be beneficial in the treatment of patients with COPD.