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61.
Carroll CN Coombs BA McClintock SP Johnson CA Berryman OB Johnson DW Haley MM 《Chemical communications (Cambridge, England)》2011,47(19):5539-5541
Urea and sulfonamide derivatives of 1 exhibit ON-OFF and OFF-ON switchable fluorescent and colorimetric responses upon protonation. The magnitude of the fluorescence event is dictated by the anion, resulting in a rare, fully organic "turn-on" fluorescent sensor for chloride. 相似文献
62.
McClintock SP Zakharov LN Herges R Haley MM 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(24):6798-6806
The cyclization reactions of naphthalene-fused azo-ene-yne compounds are explored both computationally and experimentally. Calculations reveal that naphtho-fusion to an azo-ene-yne scaffold does not significantly alter the transition state energies compared to the benzene-based systems; however, fusing the naphthalene in an angular fashion leads to lower energy intermediates due to the creation of arenes possessing greater aromaticity. Experimentally, the cyclization of the angular systems yields not only the expected monomeric benzocinnolines and benzoisoindazoles, but also several dimeric structures, including one that readily isomerizes in the presence of light and/or trace acid. 相似文献
63.
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65.
Professor Peter V.E. McClintock 《Contemporary Physics》2013,54(5):464-465
66.
C. Bayram J. L. Pau R. McClintock M. Razeghi 《Applied physics. B, Lasers and optics》2009,95(2):307-314
Growths of blue and green multi-quantum wells (MQWs) and light-emitting diodes (LEDs) are realized on lateral epitaxial overgrowth
(LEO) GaN, and compared with identical structures grown on conventional GaN. Atomic force microscopy is used to confirm the
significant reduction of dislocations in the wing region of our LEO samples before active-region growth. Differences between
surface morphologies of blue and green MQWs are analyzed. These MQWs are integrated into LEDs. All devices show a blue shift
in the electroluminescence (EL) peak and narrowing in EL spectra with increasing injection current, both characteristics attributed
to the band-gap renormalization. Green LEDs show a larger EL peak shift and a broader EL spectrum due to larger piezoelectric
field and more indium segregation in the MQWs, respectively. Blue LEDs on LEO GaN show a higher performance than those on
conventional GaN; however, no performance difference is observed for green LEDs on LEO GaN versus conventional GaN. The performance
of the green LEDs is shown to be primarily limited by the active layer growth quality. 相似文献
67.
D. G. Luchinsky V. N. Smelyanskiy M. Millonas P. V. E. McClintock 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,65(3):369-377
Population fluctuations in a predator-prey system are analyzed for the case where the number of prey could be determined,
subject to measurement noise, but the number of predators was unknown. The problem of how to infer the unmeasured predator
dynamics, as well as the model parameters, is addressed. Two solutions are suggested. In the first of these, measurement noise
and the dynamical noise in the equation for predator population are neglected; the problem is reduced to a one-dimensional
case, and a Bayesian dynamical inference algorithm is employed to reconstruct the model parameters. In the second solution
a full-scale Markov Chain Monte Carlo simulation is used to infer both the unknown predator trajectory, and also the model
parameters, using the one-dimensional solution as an initial guess. 相似文献
68.
D. A. Kenwright A. Bahraminasab A. Stefanovska P. V. E. McClintock 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,65(3):425-433
We show that the transitions which occur between close orders of synchronization in the cardiorespiratory system are mainly
due to modulation of the cardiac and respiratory processes by low-frequency components. The experimental evidence is derived
from recordings on healthy subjects at rest and during exercise. Exercise acts as a perturbation of the system that alters
the mean cardiac and respiratory frequencies and changes the amount of their modulation by low-frequency oscillations. The
conclusion is supported by numerical evidence based on a model of phase-coupled oscillators, with white noise and lowfrequency
noise. Both the experimental and numerical approaches confirm that low-frequency oscillations play a significant role in the
transitional behavior between close orders of synchronization. 相似文献
69.
S. M. Soskin P. V.E. McClintock T. M. Fromhold I. A. Khovanov R. Mannella 《Contemporary Physics》2013,54(3):233-248
Stochastic webs were discovered, first by Arnold for multi-dimensional Hamiltonian systems, and later by Chernikov et al. for the low-dimensional case. Generated by weak perturbations, they consist of thread-like regions of chaotic dynamics in phase space. Their importance is that, in principle, they enable transport from small energies to high energies. In this introductory review, we concentrate on low-dimensional stochastic webs and on their applications to quantum transport in semiconductor superlattices subject to electric and magnetic fields. We also describe a recently-suggested modification of the stochastic web to enhance chaotic transport through it and we discuss its possible applications to superlattices. 相似文献
70.
The influence of magnesium doping on the properties of tetrakis(thiourea)nickel(II) chloride crystals has been described. The reduction in the intensity observed in powder X-ray diffraction of doped specimen and slight shifts in vibrational frequencies confirm the lattice stress as a result of doping. Surface morphological changes due to doping of the alkaline earth metal are observed by scanning electron microscopy. The incorporation of Mg(II) into the crystal lattice was confirmed by energy dispersive X-ray spectroscopy. Lattice parameters are determined by single crystal XRD analysis. The thermogravimetric and differential thermal analysis studies reveal the purity of the materials and no decomposition is observed up to the melting point. The crystal is further characterized by Kurtz powder technique and dielectric studies. 相似文献