We measured the improvement in retinal image quality provided by correcting the temporal variation in the eye's wave aberration with a closed-loop adaptive optics system. This system samples the ...eye's wave aberration at rates up to 30 Hz. Correction of the eye's aberrations can be completed in 0.25-0.5 seconds, resulting in residual rms wave-front errors as low as 0.1 microns for 6.8 mm pupils. Real-time wave-front measurements were used to determine how effectively the spatial and temporal components of the eye's wave aberration were corrected. The system provides dynamic correction of fluctuations in Zernike modes up to 5 th order with temporal frequency components up to 0.8 Hz. Temporal performance is in good agreement with predictions based on theory. Correction of the temporal variation in the eye's wave aberration increases the Strehl ratio of the point spread function nearly 3 times, and increases the contrast of images of cone photoreceptors by 33% compared with images taken with only static correction of the eye's higher order aberrations.
•The purpose is to evaluate the effects of induced damage and surface modification on the surface of F82H for deuterium retention/desorption behavior.•2 types of the samples, the non-oxidized and the ...oxidized F82H, were examined.•The amount of retained deuterium of the non-oxidized F82H was larger than that of the oxidized F82H.•The desorption behavior was quite difference between the non-oxidized and the oxidized F82H.•The oxide layer of F82H greatly influenced the deuterium retention/desorption behavior.
The effects of induced damage on hydrogen isotope retention in F82H with or without thermal oxidation were investigated using thermal desorption spectroscopy. To induce damage and modify the surface, glow discharge pre-irradiated Ar+ ions was examined. In non-oxidized samples, the amount of desorbed deuterium increased with Ar+ ion fluence. Oxygen depletion in the surface layer of non-oxidized samples from the Ar+ ion irradiation, which resulted in bulk diffusion of deuterium, is responsible for the increase in deuterium retention. A comparison between non-oxidized and oxidized samples clearly indicated that the surface oxide layer greatly influenced deuterium retention/desorption behaviors of F82H.
We report great improvement of RF output power for H-terminated diamond field-effect transistors (FETs). For the FET device with a gate width of 1 mm and a gate length of 0.4 μm, the maximum output ...power (
P
out) is 1.26 W, the maximum power gain is 23.2 dB, and the power added efficiency (PAE) is 56.3%. The increase in the device temperature when output power is 0.84 W is only ∼0.6 °C. This is due to diamond having the highest thermal conductivity.
Objectives To investigate factors associated with 30-day perioperative complications (POC) after aorto-iliac (AI) stenting, and to compare follow-up cardiovascular prognosis between patients with and ...without POC. Materials and methods This was a retrospective multicenter study. We used a multicenter database of 2012 consecutive patients who successfully underwent AI stenting for peripheral arterial disease in 18 centers in Japan from January 2005 to December 2009 to analyze independent predictors of POC and impact of POC on prognosis by logistic regression and a Cox proportional hazard regression model, respectively. Results Mean age was 71 ± 9 years (median: 72 years; range: 37–98 years), and 1,636 patients (81%) were men. POC occurred in 126 patients (6.3%). In multivariate logistic regression analysis, old age (≥80 years), critical limb ischemia (CLI), and Trans Atlantic Inter-Societal Consensus (TASC) II class C/D were independently associated with POC with adjusted odds ratios and 95% confidence intervals (CI) of 1.9 (1.3–2.9), 2.3 (1.5–3.4), and 2.4 (1.6–3.4), respectively. Out of 2012 patients, 1995 were followed up for more than 30 days (mean: 2.6 ± 1.5 years; range: 2–2,393 days). In a Cox hazard regression model adjusted for baseline clinical characteristics, POC was positively and independently associated with follow-up major adverse cardiac events (adjusted hazard ratio HR: 1.9; 95% CI: 1.3–2.8; p = .002), but not with major adverse limb events and target lesion revascularization (adjusted HR: 1.4; 95% CI: 0.7–2.7; p = .25; and adjusted HR: 1.2; 95% CI 0.6–2.6; p = .568), respectively. Conclusions Age >80 years, CLI, and TASC C/D lesion were positively associated with POC after AI stenting. Occurrence of POC appears to adversely affect follow-up cardiovascular, but not limb and vessel prognosis.
DT+ ion irradiation was performed on polycrystalline tungsten, graphite and carbon film and both the amount of retained tritium and the reduction of retained tritium after preservation in vacuum were ...investigated using an IP technique and BIXS. In addition, the relationship between the retention properties of tritium and the microstructure of graphite and carbon film were studied with Raman spectroscopy. The amount of retained tritium in tungsten was smaller than in both graphite and carbon film. After 1keV of DT+ irradiation, graphite showed no reduction of the amount of retained tritium after six months preservation while that of carbon film decreased by approximately 20% after 40 days preservation. It was suggested that this difference might be associated with differences in the microstructure between graphite and carbon film. In tungsten, the amount of retained tritium decreased to approximately half after 18 days preservation. As the incident energy of implanted tritium to tungsten increased, the decrease in tritium retention during preservation became slower. Tungsten's properties of releasing tritium while preserved in vacuum would be a useful tool for the reduction/removal of retained tritium.
► Chemisorption of H2O and CO2 markedly changes the ionization potential of CaO. ► Heating in vacuum is effective to cleaning the MgO surface but not effective for CaO. ► The firing voltage of plasma ...display panels and the ionization potential correlate. ► Metastable de-excitation spectroscopy is effective to evaluating protective layers.
Changes in the ionization potential of MgO and CaO film surfaces upon heating in air and vacuum, which are necessary processes in the manufacture of plasma display panels, were investigated by metastable de-excitation spectroscopy. Heating at 500°C for 1min in vacuum is effective for cleaning an MgO film surface previously heated in air, resulting in the recovery of the ionization potential of the cleaned MgO surface from the increased value upon heating in air. A similar treatment is not effective for the CaO surface. This difference in behavior can be attributed to the stronger bonding states of H2O and CO2 on CaO than those on MgO. This is consistent with the fact that CaO has not yet been practically used as a protective layer in plasma display panels. Furthermore, the firing voltages of the plasma predicted for the MgO and CaO protective layers from the ionization potentials determined by metastable de-excitation spectroscopy were found to qualitatively agree with measured firing voltages obtained for a test panel. The present results confirmed that metastable de-excitation spectroscopy is effective for evaluating protective layers used in plasma display panels.
The structure and spin-resolved electronic states of a graphene-adsorbed Fe/Ni(1 1 1) surface are investigated and compared with a graphene/Ni(1 1 1) surface using first-principles calculations. Nine ...possible geometries are studied with Fe and C atoms at different sites with respect to the topmost Ni atoms. Geometries with one C atom located on top of an Fe atom (C1) and one at a hollow (fcc or hcp) site (C2) are the most energetically favourable. The electronic states of graphene are significantly modified by the interaction with the Fe/Ni(1 1 1) surface. The dominant π states of the C2 atom are drastically shifted towards the Fermi level and become highly positive-spin-polarized due to the corresponding spin-down states located above the Fermi level. The level shift is very small for the spin-up π states of the C1 atom but obvious for the spin-down states due to spin splitting induced by Fe atoms, resulting in a negative spin polarization at shallow levels and a positive one at deeper levels. The adsorption of graphene on Fe/Ni(1 1 1) is stronger than that on the clean Ni(1 1 1) surface.
Ionic vacancy is, being produced as a byproduct in electrode reaction, a polarized free space of the order of 0.1 nm surrounded by oppositely charged ionic cloud. As a perfect gas in electrolyte ...solution, it does not interplay with other solution particles. On the other hand, magnetic field provides useful means to examine the natures of it. Using a special electrode operated in a magnetic field called cyclotron MHD electrode (CMHDE), we first determined the lifetime of vacancy in copper deposition as 1.2 sec, which is extraordinarily long in comparison with the collision interval of solution particles. Then, using kinetic theory of gas, we measured the collision radius of vacancy gas to be 0.70 nm, which was consistent with theoretical calculation 0.65 nm.
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