1,424 research outputs found
Theoretical study of isolated dangling bonds, dangling bond wires and dangling bond clusters on H:Si(100)-(21) surface
We theoretically study the electronic band structure of isolated unpaired and
paired dangling bonds (DB), DB wires and DB clusters on H:Si(100)-(21)
surface using Extended H\"uckel Theory (EHT) and report their effect on the Si
band gap. An isolated unpaired DB introduces a near-midgap state, whereas a
paired DB leads to and states, similar to those introduced by an
unpassivated asymmetric dimer (AD) Si(100)-(21) surface. Such induced
states have very small dispersion due to their isolation from the other states,
which reside in conduction and valence band. On the other hand, the surface
state induced due to an unpaired DB wire in the direction along the dimer row
(referred to as ), has large dispersion due to the strong coupling
between the adjacent DBs, being 3.84 apart. However, in the direction
perpendicular to the dimer row (referred to as [110]), due to the reduced
coupling between the DBs being 7.68 apart, the dispersion in the surface
state is similar to that of an isolated unpaired DB. Apart from this, a paired
DB wire in direction introduces and states similar
to those of an AD surface and a paired DB wire in [110] direction exhibits
surface states similar to those of an isolated paired DB, as expected. Besides
this, we report the electronic structure of different DB clusters, which
exhibit states inside the band gap that can be interpreted as superpositions of
states due to unpaired and paired DBs.Comment: 7 pages, 10 figure, 1 tabl
Like a fish in water: Habitus adaptation mechanisms of informal tourism entrepreneurs in Thailand.
This article investigates possible pathways of habitus change by informal tourism entrepreneurs in Thailand. Bourdieu's concept of habitus is depicted as a person's understanding of the world. Do people adapt their worldview in response to only external stimuli? Through ethnographic fieldwork including participant observations and active semi-structured interviews with 53 participants, this paper identifies a classification of four modes of habitus adaptation: (1) Understanding and appreciating the field and its conditions, (2) Challenging core beliefs systems, (3) Applying a practical sense to ‘objective possibilities’, and, (4) Challenging non-reflective dispositions. We argue that charting the modes of habitus adaptation could help policymakers understand the change processes of informal entrepreneurs in the tourism sector and their willingness to change.</p
Gaseous Air Pollutants and Hospitalization for Respiratory Disease in the Neonatal Period
OBJECTIVE: Current levels of ambient air pollution are associated with morbidity and mortality in the general population. To determine the influence of gaseous air pollutants on neonatal respiratory morbidity, we tested the association between daily respiratory hospitalizations and daily concentrations of ambient air pollution gases: ozone, carbon monoxide, sulfur dioxide, and nitrogen dioxide, in 11 large Canadian cities. STUDY DESIGN: Daily time-series analyses were employed and results were adjusted for day of the week, temperature, barometric pressure, and relative humidity. RESULTS: The percent increases in hospitalization associated with an increase in air pollution equivalent to its interquartile range were 3.35 [95% confidence interval (CI), 1.73–4.77] for O(3), 2.85 (95% CI, 1.68–4.02) for NO(2), 1.66 (95% CI, 0.63–2.69) for SO(2), and 1.75 (95% CI, 0.48–3.02) for CO. The independent effect of all pollutants combined was 9.61% (95% CI, 4.52–14.7%). CONCLUSION: Our results suggest that neonates are experiencing adverse effects of air pollution at current levels in Canada, and that accounts for a significant proportion of hospitalizations in this subgroup
One- and Two-Dimensional Maximum Softening Indicators for Reinforced Concrete Structures under Seismic Excitation
Midbroken Reinforced Concrete Shear Frames Due to Earthquakes:a hysteretic model to quantify damage at the storey level
Fabrication and characterisation of electrodeposited and magnetron sputtered thin films
The MnO-Zn thin films were fabricated by radio frequency (RF) magnetron sputtering and compared with pulse electrodeposition (PED) Zn thin films, doped with MnO and ZrO nanoparticles. Surface morphology, structural properties, chemical composition and corrosion resistance of these coatings were investigated by using Scanning Electron Microscopic (SEM), X-ray Diffraction (XRD), Energy-dispersive X-ray Spectroscopy (EDS), 3-D Scanning Interferometry and environmental chamber. Surface morphology and degree of crystallinity have different behaviour for differen t deposi tion method. Pulse coated films have polycrystalline structure with high surface roughness (Ra) whereas sputtered films are mono-crystalline with reduced roughness (Ra). Corrosion tests of both RF sputter and PED films revealed that the distribution of corrosion products formed on the surface of sputter films were not severe in extent as in case of electrodeposited coatings. Results showed that the doping of ZrO nano-sized particles in Zn matrix and Mn-Zn composite films significantly improved the corrosion resistance of PED thin films
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