Active flexure

Triayer Polymer Actuator (active flexure joint)... 

Fig. 6.5. Yield strengths from flexural tests are plotted against strain rates at the surface of the samples. Tests were performed on polymers A, B, and E test temperature 23 °C. The slope of the three lines correspond to similar activation volumes v = 2 0.1 nm3...

Nickel itch is a dermatitis resulting from sensitization to nickel the first symptom is usually pruritis, which occurs up to 7 days before skin eruption appears. The primary skin eruption is erythematous, or follicular it may be followed by superficial discrete ulcers that discharge and become crusted or by eczema. The eruptions may spread to areas related to the activity of the primary site such as the elbow flexure, eyelids, or sides of the neck and face. In the chronic stages, pigmented or depigmented plaques may be formed. Nickel sensitivity, once acquired, is apparently not lost of 100 patients with positive patch tests to nickel, all reacted to the metal when retested 10 years later. ... 

Similar results were obtained (55) for the N20 crystal in the frequency region that corresponds to the combination frequency i/ + 1/3. The N2O molecule is not symmetrical and therefore all of its three intramolecular vibrations, i/, 1/2 and 1/3, are IR active. Its flexural vibration v2 is two-fold degenerate and, owing to... 

Surface chlorination can produce good barrier layers with less tendency to provide flexure failures. Unfortunately, chlorine reacts too slowly to be practical as a treatment agent in the absence of promotion by UV light. It is clearly not convenient to use UV in the interior of containers, so alternative activators were sought. Chemical activation of the chlorination reaction was shown to be possible using a mixture of 10% 303/90% CI2 as such or further diluted with air or nitrogen at 25°C. 

The effect of wood species on the wood-polymer interface and on properties of WPCs has received little attention in the literature. Stark and Berger [13] evaluated the effect of ponderosa pine, loblolly pine, maple, or oak on the mechanical properties of polypropylene WPCs. In general, WPCs made with maple or oak exhibit slightly better tensile and flexural properties and heat deflection temperatures than either of the pines. Composites elaborated with coconut flber and polyurethanes have shown good results. Coconut flber acts as reinforcement and active part of the matrix system, improving the interface... 

The embedded material should reinforce the matrix, e.g., with respect to flexural strength. Because this effect is absent with interpenetrating networks, these are often not classed as composites, although, according to structure, they are composites with a zero-dimensional dispersed phase. Polymers reinforced with active or inactive particulate fillers are also not classed as composites. 

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