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This study addresses physiological, acoustic, and linguistic issues in the production of the emphatic sounds [in text] and the pharyngeal sounds [in text]. Approximately 300 minutes of video recordings were obtained from nine Hebrew and Arabic speakers, using a fiberscope positioned in the upper pharynx and simultaneous audio recording through an external(More)
Single aerosol particles of ethylene glycol and oleic acid are vaporized on a heater at temperatures between 500 and 700 K, and the resulting vapor plume is ionized by a 10.5-eV vacuum ultraviolet (VUV) laser. The mass spectra are compared to those obtained by CO2 laser vaporization followed by VUV laser ionization. The relative intensities of the parent(More)
One of the acoustic properties distinguishing the syllable-initial stop consonant /b/ from the semivowel /w/ is the duration of the initial formant transitions; syllables beginning with /b/ have shorter transitions than those beginning with /w/. This experiment investigated the way in which the transition durations of /b/ and /w/ change as a function of(More)
The first results are reported from a new single-particle two-color laser time-of-flight mass spectrometer, incorporating a combination of infrared (CO(2)) and UV (excimer) laser irradiation. This combination of lasers has the capability to effectively separate the desorption or evaporation step from the ionization step, thereby greatly improving the(More)
A synchrotron radiation based aerosol time-of-flight mass spectrometer using tunable vacuum-ultraviolet (VUV) light is described for real-time analysis of organic compounds in ultrafine and large aerosol particles. Particles are sampled from atmospheric pressure and are focused through an aerodynamic lens assembly into the mass spectrometer. As the(More)
Single-particle kinetic studies of the reaction between oleic acid and O 3 have been conducted on two different types of core particles: polystyrene latex (PSL) and silica. Oleic acid was found to adsorb to both particle types in multilayer islands that resulted in an adsorbed layer of a total volume estimated to be less than one monolayer. The rate of the(More)
The oleic acid ozonolysis in mixed oleic and myristic acid particles was studied in a flow tube reactor using single particle mass spectrometry. The change in reactivity was investigated as a function of the myristic acid concentration in these 2 micron particles. For pure oleic acid aerosol, the reactive ozone uptake coefficient, gamma, was found to be 3.4(More)
We have compressed the output of a synchronously pumped cavity-dumped dye laser with a fiber-prism pulse compressor. The prism pair consisted of two dense flint glass prisms, which were used at a grazing exit angle to increase the dispersive power. We present the results of several experiments in which we have demonstrated 85% throughput, high compression(More)