7,952 research outputs found
Cavity ringdown laser absorption spectroscopy and time-of-flight mass spectroscopy of jet-cooled silver silicides
The cavity ringdown technique has been employed for the first spectroscopic characterization of the AgSi molecule, which is generated in a pulsed laser vaporization plasma reactor. A total of 20 rovibronic bands between 365 and 385 nm have been measured and analyzed to yield molecular properties for the X, B, and C 2Sigma states of AgSi. A time-of-flight mass spectrometer simultaneously monitors species produced in the molecular beam and has provided the first direct evidence for the existence of polyatomic silver silicides. Comparison of the AgSi data to our recent results for the CuSi diatom reveals very similar chemical bonding in the two coinage metal silicides, apparently dominated by covalent interactions
Quantitative effects of abrupt deceleration on pulmonary diffusion in man Technical report,
Quantitative effects of abrupt deceleration on pulmonary diffusion in ma
Experimental and theoretical confirmation of Bloch-mode light propagation in planar photonic crystal waveguides
The dispersion diagram of the leaky modes in the planar photonic crystal waveguide is experimentally obtained for the wavelengths from 1440 to 1590 nm. A small stop band, around wavelength 1500 nm, is detected. The experimentally obtained results are in very good agreement with our three-dimensional finite difference time domain calculations. Propagation losses of the leaky modes are estimated and we have found that they decrease as we approach the ministop band
Fast high-efficiency integrated waveguide photodetectors using novel hybrid vertical/butt coupling geometry
We report a novel coupling geometry for integrated waveguide photodetectorsâa hybrid vertical coupling/butt coupling scheme that allows the integration of fast, efficient, photodetectors with conventional double heterostructure waveguides. It can be employed to yield a planar, or pseudo-planar, surface that supports further levels of integration. The approach is demonstrated with a 25-”m-long p-i-n detector integrated with an InP/InGaAsP/InP waveguide, which displays a high (~90%) efficiency and large (~15 GHz) bandwidth. This is the fastest high-efficiency integrated waveguide photodetector reported to date
Monolithic InP-Based Grating Spectrometer for Wavelength-Division Multiplexed Systems at 1.5 ÎŒm
A monolithic InP-based grating spectrometer for use in wavelength-division multiplexed systems at 1.5 ÎŒm is reported.
The spectrometer uses a single etched reflective focusing diffraction grating and resolves >50 channels at 1 nm spacing with a ~0.3nm channel width and at least 19dB channel isolation. Operation is essentially of the state of the input polarisation
On the ground electronic states of copper silicide and its ions
The low-lying electronic states of SiCu, SiCu^+, and SiCu^â have been studied using a variety of high-level ab initio techniques. As expected on the basis of simple orbital occupancy and bond forming for Si(s^2p^2)+Cu(s^1) species, ^2Î _r, ^1ÎŁ^+, and ^3ÎŁ^â states were found to be the ground electronic states for SiCu, SiCu^+, and SiCu^â, respectively; the ^2Î _r state is not that suggested in most recent experimental studies. All of these molecules were found to be quite strongly bound although the bond lengths, bond energies, and harmonic frequencies vary slightly among them, as a result of the nonbonding character of the 2Ï-MO (molecular orbital) [composed almost entirely of the Si 3p-AO (atomic orbital)], the occupation of which varies from 0 to 2 within the ^1ÎŁ^+, ^2Î _r, and ^3ÎŁ^â series. The neutral SiCu is found to have bound excited electronic states of ^4ÎŁ^â, ^2Î, ^2ÎŁ^+, and ^2Î _i symmetry lying 0.5, 1.2, 1.8, and 3.2 eV above the ^2Î _r ground state. It is possible but not yet certain that the ^2Î _i state is, in fact, the âB stateâ observed in the recent experimental studies by Scherer, Paul, Collier, and Saykally
Recognizing Emotions in a Foreign Language
Expressions of basic emotions (joy, sadness, anger, fear, disgust) can be recognized pan-culturally from the face and it is assumed that these emotions can be recognized from a speaker's voice, regardless of an individual's culture or linguistic ability. Here, we compared how monolingual speakers of Argentine Spanish recognize basic emotions from pseudo-utterances ("nonsense speech") produced in their native language and in three foreign languages (English, German, Arabic). Results indicated that vocal expressions of basic emotions could be decoded in each language condition at accuracy levels exceeding chance, although Spanish listeners performed significantly better overall in their native language ("in-group advantage"). Our findings argue that the ability to understand vocally-expressed emotions in speech is partly independent of linguistic ability and involves universal principles, although this ability is also shaped by linguistic and cultural variables
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