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61.
The integration of voice science, voice pathology, medicine, public speaking, acting, and singing has been central to evolution in all fields. The Voice Foundation Symposia have played a seminal and central role in fostering integration among disciplines. The result has been an improvement in the knowledge and practice in each field. And the future promises to be even more informative and exciting.  相似文献   
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Absorption and emission spectra at room temperature and emission spectra atliquid nitrogen temperature are reported for thin solid films of free base octaethylporphin. The room temperature visible absorption spectrum resembles that of the solution, except all four peaks show a red shift of ≈ 12 nm and all except the farthest red are broadened. The Soret band in the near UV is greatly broadened in the film, and its peak absorbance is substantially reduced. The room-temperature emission of the films is quite similar to that of solution fluorescence, except for a red-shift of ≈ 10 nm. But at low temperature two new peaks appear at 657 and 672 nm. Their intensity as a function of temperature can be explained by a simple exciton trapping model.  相似文献   
64.
In a previous paper, which appeared in two parts, Algorithm I was described. (See [1] and [2] for details). Algorithm II differs from Algorithm I in that the Chinese Remainder Theorem is not used whenever it is necessary to reconstruct a unique integer from its residue representation. Instead, the residue representation is converted to asymmetric residue representation and then the symmetric residue representation is converted to its associatedsymmetric mixed-radix representation, from which the unique integer can be reconstructed in an easy manner. This procedure has advantages over the procedure using the Chinese Remainder Theorem.  相似文献   
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The syllable repetitions of 24 child and eight teenage stutterers were investigated to assess whether the vowels neutralize and, if so, what causes this. In both groups of speakers, the vowel in CV syllable repetitions and the following fluent vowel were excised from conversational speech samples. Acoustic analyses showed the formant frequencies of vowels in syllable repetitions to be appropriate for the intended vowel and the duration of the dysfluent vowels to be shorter than those of the fluent vowels for both groups of speakers. The intensity of the fluent vowels was greater than that of the dysfluent vowels for the teenagers but not the children: For both age groups, excitation waveforms obtained by inverse filtering showed that the excitation spectra associated with dysfluent vowels fell off more rapidly with frequency than did those associated with the fluent vowels. The fundamental frequency of the children's dysfluent speech was higher than their fluent speech while there was no difference in the teenager's speech. The relationship between the intensities of the glottal volume velocities was the same as that of the speech waveforms. Perceptual tests were also conducted to assess whether duration and the differences found in the source excitation would make children's vowels sound neutral. The experiments show that in children neither vowel duration nor fundamental frequency differences cause the vowels to be perceived as neutral. The results suggest that the low intensity and characteristics of the source of excitation which cause vowels to sound neutral may only occur in late childhood. Furthermore, monitoring stuttered speech for the emergence of neutral vowels may be a way of indexing the progress of the disorder.  相似文献   
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There are numerous articles wherein mathematical models of various parts of an in situ hearing aid have been reported. Such parts include, for example, the microphone, receiver, cylindrical tubes carrying sound to the eardrum and out through the earmold vent, and the external path from the vent back to the microphone. This article extends these earlier works to include the hearing-aid amplifier. In particular, a mathematical technique for characterizing the amplifier in combination with the receiver is reported. Cascade parameters of a two-port model of one particular amplifier/receiver combination are obtained by this method. The cascade-parameter data and the method of obtaining this data are verified by two different experimental procedures. One procedure involves both computing and measuring the input driving-point impedance of the amplifier/receiver combination. In the second procedure, the amplifier-to-eardrum transfer function of a hearing aid incorporating this same amplifier/receiver combination and mounted on an artificial ear is both computed and measured. Experimental and computed values of this transfer function for three different earmold geometries are in reasonably close agreement. The amplifier/receiver model reported herein will be used in future studies of acoustic feedback in hearing aids.  相似文献   
69.
A novel electrograft method of forming covalent bonds directly to silicon hydride or platinum surfaces has been demonstrated with the use of iodonium salt precursors. Initially, a silicon substrate is treated with a dilute hydrofluoric acid wash to ensure a hydride-passivated surface, which is immersed in a solution of iodonium salt dissolved in a solution of tetrabutylammonium tetrafluoroborate in acetonitrile. Grafting is accomplished by applying a negative bias to the silicon substrate. Directed assembly has been demonstrated with Pt substrates.  相似文献   
70.
Calcium and magnesium carbonates are important minerals found in sedimentary environments. Although sandstones are the most common rock colonized by endolith organisms, the production of calcium and magnesium carbonates is important in survival strategies of organisms and as a source for the removal of oxalate ions. Extremophile organisms in some situations may convert or destroy carbonates of calcium and magnesium, which gives important information about the conditions under which these organisms can survive. The identification on the surface of Mars of 'White Rock' formations, in Juventae Chasma or Sabaea Terra, as possibly carbonate rocks makes the study of these minerals a prerequisite of remote Martian exploration. Here, we show the protocol for the identification by Raman spectroscopy of different calcium and magnesium carbonates and we present a database of relevance in the search for life, extinct or extant, on Mars; this will be useful for the assessment of data obtained from remote, miniaturized Raman spectrometers now proposed for Mars exploration.  相似文献   
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