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101.
A. Kress F. Hofbauer N. Reinelt H.J. Krenner M. Bichler D. Schuh R. Meyer G. Abstreiter J.J. Finley 《Physica E: Low-dimensional Systems and Nanostructures》2005,26(1-4):351
We demonstrate our ability to control and manipulate the optical modes in 2D Photonic Crystal Defect cavities and investigate their coupling to InGaAs self-assembled quantum dots. Our results enable us to probe the nature of individual cavity modes and directly investigate cavity QED phenomena. For the lowest mode volume cavities investigated, consisting of a single missing air hole within a hexagonal lattice, we have measured a clear Purcell enhancement of the light-matter interaction in the weak coupling regime. For QDs on-resonance with localized cavity modes this translates to a shortening of the quantum dot spontaneous emission lifetime by a factor 2 when compared to off-resonance dots. 相似文献
102.
C. Besse M. Ehrhardt I. Lacroix‐Violet 《Numerical Methods for Partial Differential Equations》2016,32(5):1455-1484
We consider the derivation of continuous and fully discrete artificial boundary conditions for the linearized Korteweg–de Vries equation. We show that we can obtain them for any constant velocities and any dispersion. The discrete artificial boundary conditions are provided for two different numerical schemes. In both continuous and discrete case, the boundary conditions are nonlocal with respect to time variable. We propose fast evaluations of discrete convolutions. We present various numerical tests which show the effectiveness of the artificial boundary conditions.© 2016 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 32: 1455–1484, 2016 相似文献
103.
Solid-phase extraction has become one of the most commonly used techniques for preconcentration of analytes from environmental samples. In the standard use of solid sorbent phases the extracted pollutants are subsequently eluted with a suitable organic solvent before chromatographic analysis. An alternative to this procedure is analysis of the adsorbed and concentrated pollutants by direct application of a spectroscopic method (fluorimetry or absorptiometry) to the phase. Although this method cannot be expected to give results as precise as those given by chromatographic methods, it might have valuable applications, particularly for "on site" pollution monitoring. This paper reports an evaluation of the capability of the method for the spectrophotometric detection of BTX (benzene, toluene, xylenes) in aqueous media and in contaminated atmospheres, with polydimethylsiloxane (PDMS) as sorbent. The tests performed, with the estimated detection limits, indicate that the method is relatively simple and easy to operate and sensitive enough for application to the monitoring of pollution both in water and in air in an industrial ambient atmosphere. 相似文献
104.
105.
106.
Aguilar-Arevalo AA Bazarko AO Brice SJ Brown BC Bugel L Cao J Coney L Conrad JM Cox DC Curioni A Djurcic Z Finley DA Fleming BT Ford R Garcia FG Garvey GT Green C Green JA Hart TL Hawker E Imlay R Johnson RA Kasper P Katori T Kobilarcik T Kourbanis I Koutsoliotas S Laird EM Link JM Liu Y Liu Y Louis WC Mahn KB Marsh W Martin PS McGregor G Metcalf W Meyers PD Mills F Mills GB Monroe J Moore CD Nelson RH Nienaber P Ouedraogo S Patterson RB Perevalov D Polly CC Prebys E Raaf JL Ray H Roe BP 《Physical review letters》2008,100(3):032301
107.
Xia Q Lee MV Rose CM Marsh AJ Hubler SL Wenger CD Coon JJ 《Journal of the American Society for Mass Spectrometry》2011,22(2):255-264
Using a large set of high mass accuracy and resolution ETD tandem mass spectra, we characterized ETD-induced neutral losses.
From these data we deduced the chemical formula for 20 of these losses. Many of them have been previously observed in electron-capture
dissociation (ECD) spectra, such as losses of the side chains of arginine, aspartic acid, glutamic acid, glutamine, asparagine,
leucine, histidine, and carbamidomethylated cysteine residues. With this information, we examined the diagnostic value of
these amino acid-specific losses. Among 1285 peptide–spectrum matches, 92.5% have agreement between neutral loss-derived peptide
amino acid composition and the peptide sequences. Moreover, we show that peptides can be uniquely identified by using only
the accurate precursor mass and amino acid composition based on neutral losses; the median number of sequence candidates from
an accurate mass query is reduced from 21 to 8 by adding side chain loss information. Besides increasing confidence in peptide
identification, our findings suggest the potential use of these diagnostic losses in ETD spectra to improve false discovery
rate estimation and to enhance the performance of scoring functions in database search algorithms. 相似文献
108.
A new procedure for the reduction of Preston tube data is introduced, based on the van Driest transformation. It appears to give results agreeing with the better calibration experiments, although a significant assumption in its derivation is violated.List of Symbols
M
s
Mach number sensed by Preston tube
-
M
Friction Mach number (=u/wall sound speed)
-
R
Gas constant
-
T
w
Wall temperature
-
d
Diameter of Preston tube
-
h
Height of effective centre of Preston tube
-
p
Preston tube pressure difference reading
-
p
i
Equivalent incompressible Preston tube reading
-
p
w
Wall pressure
-
r
Recovery factor (=0.896)
- u
Friction velocity (=[w/wall density]1/2)
-
Empirical constant allowing for departure from Crocco temperature-velocity correlation (=0.975)
-
Specific heat ratio
-
Fluid kinematic viscosity
-
w
Wall shear-stress 相似文献
109.
Various untabbed, thickness-tapered compression specimen geometries were studied experimentally. Both shear-loaded and end-loaded compression test methods were used to measure the strength and stiffness of carbon/epoxy and glass/epoxy unidirectional composite material systems. The compressive strength was found to be strongly dependent on specimen geometry, loading conditions, and the cracks that initiated in the taper regions and propagated to various lengths prior to catastrophic failure. A specific thickness-tapered specimen geometry that produced compressive strengths significantly higher than conventional specimen configurations resulted from the experimental optimization process. A method of determining compressive strains, and thus the compressive modulus, using this same specimen geometry and strain gages was also demonstrated. 相似文献