Search results for " defect"
showing 10 items of 767 documents
Paramagnetic germanium-related centers induced by energetic radiation in silica based devices
2009
In-situ observation of β-ray induced optical absorption in a-SiO2: radiation darkening and room temperature recovery
2008
Bright blue emission of synthesized silica nanoparticles conferred by surface defects
2013
Inhomogeneous properties of defects in amorphous silica probed by time-resolved luminescence
2008
Inhomogeinity of Oxygen deficient centers in silica probed by nanosecond time-resolved luminescence measurements
2008
Resonance Raman of oxygen dangling bonds in amorphous silicon dioxide
2017
We investigate the origin of a resonance Raman band induced by ionizing radiation in amorphous silicon dioxide (silica glass), which can be detected under ultraviolet laser excitation. A silica sample, rich of oxygen-excess related defects, was prepared by treating some length of a pure-silica-core multimode fiber in an O2 atmosphere (at high temperature and pressure) and by irradiating it with X-rays at 10 MGy(SiO2) dose. A micro-Raman study revealed a gaussian band peaking at 896 cm−1 with a full width at half maximum of 32 cm−1, which could be detected by exciting the sample with the 325-nm line of a HeCd laser. This spectral feature is absent in the Raman spectra performed with the 442-…
Histopathological parameters reported in microinvasive oral squamous cell carcinoma:a systematic review
2022
Microinvasive oral squamous cell carcinoma (OSCCmi) is an incipient stage of oral cancer. Through this systematic review, we aim to assess patterns of histopathological outcomes reported in OSCCmi cases. An online search in major databases was performed without period restriction, and 2,024 publications in English, Spanish and Portuguese were obtained. After screening and eligibility, 4 studies were selected. The risk of bias was assessed using Joanna Briggs Institute Critical Appraisal Checklist. A descriptive synthesis was conducted. All 4 publications included were retrospective, reporting a total of 116 OSCCmi patients, with a male predominance (1.6:1) and a mean age of 55.9 years. The …
Luminescence Properties of Non Bridging Oxygen Hole Centers at a Silica Surface
2008
UV-VISIBLE LUMINESCENCE OF SILICA NANOPARTICLES
Excitation energies and photoabsorption oscillator strengths of the Rydberg series in CF3Cl. A linear response and quantum defect study.
2007
Vertical excitation energies of the CF(3)Cl molecule have been obtained from a response function approach with a CC reference function to determine absolute photoabsorption oscillator strengths in the molecular-adapted quantum defect orbital formalism (MQDO). The present work covers more highly excited Rydberg states than have been experimentally reported. Assessing of the reliability of the present calculations is provided through a comparative analysis between the results of the molecule and the Cl atom. This can be used to allow for predictions of the same type of properties in other analogous systems.