The mucus layer on the vocal folds was examined by videostrobolaryngoscopy in patients with laryngeal tension-fatigue syndrome, a chronic functional dysphonia due to vocal abuse and misuse. Besides the findings in previous reports (such as abnormal glottal closure, phase or amplitude asymmetry, and the irregular mucosal wave), the vocal folds during vibration had an uneven mucus surface. The occurrence of an uneven mucus layer on vocal folds was significantly greater in subjects with this voice disorder (83% or 250 of 301 patients in this series) than in those without voice disorders (18.5% or 5 of 27). The increase of mucus viscosity, mucus aggregation, and the formation of rough surfaces on the vocal folds alter the mechanical properties that contribute to vibration of the cover of the vocal folds, and thereby worsen the symptoms of dysphonia in patients with laryngeal tension-fatigue syndrome.

The isothermal-oxidation behavior of Ti 50 Ni 40 Cu 10 shape memory alloy (SMA) in 700-1,000°C air was investigated by TGA, XRD, SEM and EPMA. Experimental results indicate that a multi-layered oxide scale formed, consisting of an outermost Cu 2 O(Ni,Ti) layer, a layer of the mixture of TiO 2 , TiNiO 3 and irregular small pores, a layer of the mixture of Ni(Ti,Cu), TiO 2 and irregular large pores, a Ti(Ni,Cu) 3 layer and an innermost Ti 30 Ni 43-47 Cu 27-23 layer. The apparent activation energy for the oxidation reaction of Ti 50 Ni 40 Cu 10 SMA is determined to be 180 kJ/mol, and the oxidation rate follows a parabolic law. A schematic oxidation mechanism of Ti 50 Ni 40 Cu 10 SMA is proposed to explain the observed results.

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This study investigates the cold-rolling effect on the formation of Ti(Ni,Cu) 2 precipitates and on the change of transformation temperatures for hot-rolled (HR)/annealed (HRA) and HR/cold-rolled/annealed (CRA) Ti 50 Ni 40 Cu 10 specimens. Particle-like Ti(Ni,Cu) 2 precipitates formed in CRA are more numerous and smaller than plate-like Ti(Ni,Cu) 2 precipitates formed in HRA and thus the hardness and storage modulus of the former are higher. The broader transformation peaks exhibited in CRA compared to HRA can be explained by the assistance of the tensile stress field around the plate-like Ti(Ni,Cu) 2 precipitates. The different transformation peak temperatures of B2!B19 and B19!B19 0 in between HRA and CRA result from the different Cu content in the matrix. A relaxation peak appears in CRA with the activation energy of 64.4 kJ/mol. The cold-rolling process may be an important factor in enhancing the appearance of the relaxation peak.