17 research outputs found
Spectra of W-W in the 12 nm to 20 nm region observed with an EBIT light source
We observed spectra of highly ionized tungsten in the extreme ultraviolet
with an electron beam ion trap (EBIT) and a grazing incidence spectrometer at
the National Institute of Standards and Technology. Stages of ionization were
distinguished by varying the energy of the electron beam between 2.1 keV and
4.3 keV and correlating the energies with spectral line emergence. The spectra
were calibrated by reference lines of highly ionized iron produced in the EBIT.
Identification of the observed lines was aided by collisional-radiative
modeling of the EBIT plasma. Good quantitative agreement was obtained between
the modeling results and the experimental observations. Our line
identifications complement recent results for W-W observed in a
tokamak plasma by P\"{u}tterich {\it et al} (\jpb {\bf 38}, 3071, 2005). For
most lines we agree with their assignment of ionization stage. Additionally, we
present new identifications for some allowed and forbidden lines of W,
W, W, and W. The uncertainties of our wavelengths range
from 0.002 nm to 0.010 nm.Comment: 19 pages, 8 figure
Surface discoloration of restorative resins in relation to surface softening and oral hygiene
Computational learning of the conditional phase-type (C-Ph) distribution: Learning C-Ph distributions
Efficiency-aware and fairness-aware joint-layer optimization for downlink data scheduling in OFDM
Die Wirkung der Crataeguss�uren auf den ven�sen Blutmilchs�urespiegel des Menschen w�hrend und nach dosierter Arbeit am Ergometer
Effect of different light-curing devices and aging procedures on composite knoop microhardness
The aim of this study was to evaluate the effect of light-curing devices (Halogen/HAL, Light Emitting Diodes/LED, Argon Laser/LAS and Plasma Arc/PAC) and aging procedures (Mechanical Cycling/MC, Thermal Cycling/TC, Storage/S, MC+TC and MC+TC+S) on the micro-hardness of bottom/B and top/T surfaces of 2-mm-high composite resin cylinders. The Knoop microhardness test (25 g, 20 s) on both B and T was performed before and after each aging procedure. For B and T, before aging procedures, PAC showed reduced polymerization effectiveness when compared with HAL. In the T, after TC, PAC and LAS had also showed reduced polymerization effectiveness when compared to HAL and LED. For all light-curing devices, MC+TC+S and S affected the Knoop microhardness values. In the B, no difference could be observed among the aging procedures for PAC. From all light-curing units, PAC may have rendered composites of reduced quality and the storage aging procedures were the most harmful to the polymer hardness