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131.
Re-examination of flexible fiberoptic videotaped laryngeal images of 39 patients with unilateral recurrent laryngeal nerve paralysis (URLNP) by four observer-judges revealed consistent findings of a unilaterally appearing shorter vocal fold with asymmetry of the arytenoid complex on the involved side. No previous similar experience in otolaryngological training or practice has been encountered. Multiple discrepancies between and among observer-judges regarding vocal fold positions during phonation were encountered. Possible explanations are discussed. The need for further investigation to determine the mechanics causing these differences is stressed. It is suggested that for the present, such terms as median, paramedian, and intermediate be used in teaching and in practice as generalities only. 相似文献
132.
133.
Major criteria for a successful binaural reproduction are not only a suitable localization performance, but also the authenticity and plausibility of the presented scene. It is therefore interesting to examine whether the binaural reproduction can be perceptually distinguished from a real source. The aim of the presented investigation is to compare the quality of the binaural reproduction via headphones with two different microphone setups (miniature microphone in Open-Dome and ear plug) for individual head-related-transfer-function (HRTF) and headphone-transfer-function (HpTF) measurements. Listening tests with a total of 80 subjects were carried out focusing on plausibility and authenticity. In the examination of plausibility detection rates showed that subjects were not able to match the reproduced pink noise to its reproduction system (real source vs. binaural reproduction via headphones). The authenticity of the static binaural reproduction was highly dependent on the stimulus. Pink noise could often be distinguished due to coloration in higher frequencies and small differences in location. A difference between microphone setups could not be found in neither of the listening tests. 相似文献
134.
Pyrolysis (Py)-GC/MS was applied to differentiate between automobile paint samples. The method was used for analysis of 36 samples of styrene acrylic urethane clearcoats that were indistinguishable on the basis of their infrared spectra and elemental composition. Differences observed in the obtained pyrograms of the compared paint samples were relatively small. Therefore, statistical analysis of the obtained results was performed. The likelihood ratio test suitable for multivariate data analysis supported by analysis of data structure by graphical model was used. This approach allowed not only distinguishing the samples compared, but also allowed the evaluation of the evidential value of such observations, which is very important from a forensic point of view. 相似文献
135.
Pyrolysis (Py)-GC/MS was applied in comparative analysis of polymer binder of 150 automobile clearcoat samples. It was found that binders of identical type and similar infrared spectra can be, in most cases, effectively differentiated, sometimes based only on the presence of peaks of very low intensity originating from minor paint components. The qualitative procedure of pyrograms comparison was developed. The results obtained, enable one to draw the conclusion that Py-GC/MS appears as valuable, very informative analytical technique of car paint samples examination. Providing identification of paint pyrolysis products, it enables discrimination of samples on the basis of their composition. However, in some cases, paint samples were still indistinguishable on the basis of their pyrograms. 相似文献
136.
Zdzisaw Latajka Grzegorz Gajewski Austin J. Barnes Henryk Ratajczak 《Journal of Molecular Structure》2008,880(1-3):48
Polarizability and first hyperpolarizability values of the hydrogen-bonded complexes formed by nitrosubstituted phenols with ammonia have been calculated using PM3 and ab initio (STO-3G) methods. It has been shown that enhancement of the polarizability (Δα) as well as the first hyperpolarizability (Δβ) of the complex arises from the hydrogen bond interaction between the phenol derivative and ammonia. 相似文献
137.
The Ramsey numbers of cycles imply that every 2‐edge‐colored complete graph on n vertices contains monochromatic cycles of all lengths between 4 and at least . We generalize this result to colors by showing that every k‐edge‐colored complete graph on vertices contains ‐edge‐colored cycles of all lengths between 3 and at least . 相似文献
138.
139.
FTIR spectroscopy, atomic force microscopy (AFM) and electro-optical measurements were used to study nanocomposites consisting of nematic liquid crystal (LC) ZLI-2293 and organophilic montmorillonite (MMT) nanoparticles. The initial MMT was modified by two different surfactants: octadecylbenzyldimethylammonium chloride (OBDM) and dioctadecylldimethylammonium chloride (DODM). According to spectroscopic results, Van der Waals interactions between the components of the LC/clay composites are stronger in OBDM-MMT case. AFM images of two types of the LC/clay nanocomposites showed different morphology consisting of large-scale structures. Correlation between the spectroscopic results and electro-optical behaviour of the LC/clay nanocomposites was observed. It was inferred that the memory effect is more pronounced for composites with OBDM-MMT due to colloid network formation, whereas the electro-optical contrast is higher for DODM-MMT, where the clay particles are not organized in any ordered structure. 相似文献
140.
Photoreactive UV-crosslinkable acrylic pressure-sensitive adhesives containing type-II photoinitiators 总被引:1,自引:0,他引:1
UV-crosslinking is an established technology used in many industrial manufacturing processes. New applications and technical specifications of UV technologies stimulate the continuous development of photoinitiators that can efficiently meet specific requirements. A typical class of radical-reactive type-II photoinitiators has been used for the UV-initiated crosslinking of acrylic pressure-sensitive adhesives (PSAs).The activity of type-II photoinitiators such as: benzophenone derivatives, thioxanthone derivative, antraquinone derivative and fluorenone (without tertiary amine as a co-initiator) in the photoreactive UV-crosslinkable acrylic pressure-sensitive adhesives was described. The effect of the type-II photoinitiators on the acrylic PSA properties (tack, peel, and shear strength) was summarized. 相似文献