699 research outputs found
Fluorescence quenching of versatile fluorescent probes based on strongly electron-donating distyrylbenzenes responsive to aromatic chlorinated and nitro compounds, boronic acid and Ca2+
ArticleSPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY. 69(1): 167-173journal articl
Flexible control of the Peierls transition in metallic C polymers
The metal-semiconductor transition of peanut-shaped fullerene (C)
polymers is clarified by considering the electron-phonon coupling in the uneven
structure of the polymers. We established a theory that accounts for the
transition temperature reported in a recent experiment and also suggests
that is considerably lowered by electron doping or prolonged irradiation
during synthesis. The decrease in is an appealing phenomenon with regard
to realizing high-conductivity C-based nanowires even at low
temperatures.Comment: 3 pages, 3 figure
Large bandwidth, highly efficient optical gratings through high index materials
We analyze the diffraction characteristics of dielectric gratings that
feature a high index grating layer, and devise, through rigorous numerical
calculations, large bandwidth, highly efficient, high dispersion dielectric
gratings in reflection, transmission, and immersed transmission geometry. A
dielectric TIR grating is suggested, whose -1dB spectral bandwidth is doubled
as compared to its all-glass equivalent. The short wavelength diffraction
efficiency is additionally improved by allowing for slanted lamella. The
grating surpasses a blazed gold grating over the full octave. An immersed
transmission grating is devised, whose -1dB bandwidth is tripled as compared to
its all-glass equivalent, and that surpasses an equivalent classical
transmission grating over nearly the full octave. A transmission grating in the
classical scattering geometry is suggested, that features a buried high index
layer. This grating provides effectively 100% diffraction efficiency at its
design wavelegth, and surpasses an equivalent fused silica grating over the
full octave.Comment: 15 pages, 7 figure
Photochemical behavior of some p-styryistilbenes and related compounds: Spectral properties and photoisomerization in solution and in solid state
Author Posting. © The Authors (2006) This is the author's version of the work. It is posted here for personal use, not for redistribution. The definitive version was published in PHOTOCHEMISTRY AND PHOTOBIOLOGY, 82(6): 1645-1650. https://doi.org/10.1562/2006-01-17-RA-780ArticlePhotochemistry and Photobiology. 82(6): 1645-1650 (2006)journal articl
Charged particle display
An optical shutter based on charged particles is presented. The output light
intensity of the proposed device has an intrinsic dependence on the
interparticle spacing between charged particles, which can be controlled by
varying voltages applied to the control electrodes. The interparticle spacing
between charged particles can be varied continuously and this opens up the
possibility of particle based displays with continuous grayscale.Comment: typographic errors corrected in Eqs (37) and (39); published in
Journal of Applied Physics; doi:10.1063/1.317648
Different photochemical behavior of bis(biphenyl)ethylenes and ethenes in solution and in the solid-state: Structurally controlled Z/E-photoisomerization in the solid-state
ArticleJOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY. 184(1-2): 44-49 (2006)journal articl
Poly(benzyl ether) dendrimers with strongly fluorescent distyrylbenzene cores as the fluorophores for peroxyoxalate chemiluminescence: insulating effect of dendritic structures on fluorescent sites
ArticleTETRAHEDRON. 61(46): 11020-11026 (2005)journal articl
Semaphorin 3A regulates alveolar bone remodeling on orthodontic tooth movement
Semaphorin 3A (Sema3A) promotes osteoblast differentiation and inhibits osteoclast differentiation. In the present study, we observed the regulation of alveolar bone remodeling by Sema3A during orthodontic tooth movement (OTM). Four inflammatory cytokines (IL-1β, IL-6, TNFα, and INF-γ) involved in OTM were applied to osteoblasts in vitro, and Sema3A expression was determined by reverse-transcription quantitative polymerase chain reaction (RT-qPCR). In vivo, springs were attached to the maxillary first molars of C56BL/6J mice (OTM model) and the localization of Sema3A was confirmed by immunofluorescent. Recombinant Sema3A (rSema3A) was locally injected into the OTM model. Inflammatory cytokine localization in the OTM model was confirmed by immunohistochemistry. In vivo, more Sema3A was observed on the tension side in the OTM group. Injection of rSema3A into the OTM model increased mineralization on the tension side and decreased the number of osteoclasts on the compression side. In vitro, IL-1β significantly increased Sema3A mRNA levels. Immunohistochemistry for IL-1β in vivo showed more concentrated staining in the periodontal ligament on the tension side than on the compression side. In summary, our findings revealed the distribution of Sema3A in the periodontal ligament and demonstrated that rSema3A administration promotes bone formation and inhibits bone resorption during OTM
Stability of Ge-related point defects and complexes in Ge-doped SiO_2
We analyze Ge-related defects in Ge-doped SiO_2 using first-principles
density functional techniques. Ge is incorporated at the level of ~ 1 mol % and
above. The growth conditions of Ge:SiO_2 naturally set up oxygen deficiency,
with vacancy concentration increasing by a factor 10^5 over undoped SiO_2, and
O vacancies binding strongly to Ge impurities. All the centers considered
exhibit potentially EPR-active states, candidates for the identification of the
Ge(n) centers. Substitutional Ge produces an apparent gap shrinking via its
extrinsic levels.Comment: RevTeX 4 pages, 2 ps figure
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