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Rubber band effect

On achievement of a band of compound running around the mill roll, the compound is cut off from the front of the mill and is fed up into a feeder unit which traverses back and forth before the two driven rollers of the blender. By this action the rubber is effectively randomly worked and blended as it passes from the blending unit back down into the nip of the mill. [Pg.196]

Form a hypothesis about the effect of heat on a stretched rubber band. [Pg.2]

Almost every biological solution of low viscosity [but also viscous biopolymers like xanthane and dilute solutions of long-chain polymers, e.g., carbox-ymethyl-cellulose (CMC), polyacrylamide (PAA), polyacrylnitrile (PAN), etc.] displays not only viscous but also viscoelastic flow behavior. These liquids are capable of storing a part of the deformation energy elastically and reversibly. They evade mechanical stress by contracting like rubber bands. This behavior causes a secondary flow that often runs contrary to the flow produced by mass forces (e.g., the liquid climbs the shaft of a stirrer, the so-called Weissenberg effect ). [Pg.28]

Under regular light, it is difficult to see the waves traveling back and forth. For a better view, pluck the rubber band in front of a computer monitor or a television screen that uses a cathode ray tube. The light from these devices, which acts like a strobe light, makes the waves appear to slow down Vary the tension in the rubber band to see different effects. [Pg.157]

In elastomer samples with macroscopic segmental orientation, the residual dipolar couplings are oriented as well, so that also the transverse relaxation decay depends on orientation. Therefore, the relaxation rate 1/T2 of a strained rubber band exhibits an orientation dependence, which is characteristic of the orientational distribution function of the residual dipolar interactions in the network. For perfect order the orientation dependence is determined by the square of the second Legendre polynomial [14]. Nearly perfect molecular order has been observed in porcine tendon by the orientation dependence of 1/T2 [77]. It can be concluded, that the NMR-MOUSE appears suitable to discriminate effects of macroscopic molecular order from effects of temperature and cross-link density by the orientation dependence of T2. [Pg.281]

Fig. 10.2.3 Stress images of rubber bunds wiih a cut after correction tor spin density and relaxation effects, (a) H douhle-quantum (iltcrcd image ol poly(isopicnc) Sch6). (b) H double-quantum image at zi = I..1 of deulerated butadiene oligomers incorporated into a rubber band by swelling, (c) l-FM calculation of stress in a sample similar to (h) lKli2. ... Fig. 10.2.3 Stress images of rubber bunds wiih a cut after correction tor spin density and relaxation effects, (a) H douhle-quantum (iltcrcd image ol poly(isopicnc) Sch6). (b) H double-quantum image at zi = I..1 of deulerated butadiene oligomers incorporated into a rubber band by swelling, (c) l-FM calculation of stress in a sample similar to (h) lKli2. ...
You can easily perform the following experiments with a rubber band that is at least 0.5 cm wide. Quickly stretch the rubber band and then press it against your lips. You will feel a slight warming effect. Next, reverse the process. Stretch a rubber band and hold it in position for a few seconds. Then quickly re-... [Pg.748]

When the tension is removed, the stretched rubber band spontaneously snaps back to its original shape that is, AG is negative and -AG is positive. The cooling effect means that it is an endothermic process (AH > 0), so that TAS is positive. Thus the entropy of the rubber band increases when it goes from the stretched state to the natural state. [Pg.749]

The procedure was developed by Smithies [12] and represents the first application of an electrophoretic procedure in combination with a sieving effect. The apparatus for this purpose is very simple. It consists of two buffer vessels with platinum electrodes and a gel tray placed between them. The contact of the gel layer with electrode buffers is ensured by wicks of thick chromatographic paper. The gel tray is composed of a plastic base (about 10 x 15 cm) and two identical frames placed on top of each other. The whole system is held together by rubber bands. There are several commercially available instruments of this type (e.g.. Desaga Disaphor, Savant Model HGE 312) all provided with a cooling system. [Pg.427]

To add further excitement to the field, elongated H-H bonds of over 1A were found around 1990. Until then only dm in the range 0.85-0.90 A had been observed by solid state NMR and diffraction methods (after correction for H2 librational motion). Elongated is of course a relative term since the H-H bond is always stretched to some degree on coordination. Thus not only can a chemical bond be snapped like rope, it can effectively be stretched like a rubber band until the bond is virtually gone, i.e., a dihydride forms as shown in Eq. (1.6). A large number of... [Pg.9]

UFT Two strips ofgoid card (cardboard) are slotted together m a manner similar to variation It of the Trellis technique, then bent into a circle to create the star effect. A rubber band holds We construction m shape. When flattened, the band stretches. If the pressure on the flat card is released, the band ccmtracts and the card spnngs dramaticslly into shape. [Pg.146]

RIGHT Designed as a promotional item, the house is a basic square-on box with simple additions. The design folds flat for mailing. When removed from its envelope, a powerful rubber band, which was stretched taut, begins to contract and automatically erects the house with great speed, and dramatic effect ... [Pg.151]

A commercial grade of high-impact (notched Izod > 900 J/m) POM resin (Delrin 100 ST, DuPont) is believed to be a blend of POM with >30 wt% of a thermoplastic poly(ester-urethane) elastomer derived from poly(l, 4-butane adipate) diol and methylene-bis-(4,4 -diphenyl diisocyanate) (MDl) (Hexman 1989). This blend is reported to have a cocontinuous or semi-interpenetrating network of the elastomer in a matrix of the polyacetal (Flexman et al. 1990). The toughening effect in such a blend of IPN-type morphology was interpreted to occur partly through a rubber band mechanism by which the fracture energy is absorbed. The bands of rubbery domains were believed to span the crack and participate in the deformation process. [Pg.1835]

In the first series of experiments, 0.1 ml of the neat solvents were applied with a pipette to the forearm skin of healthy subjects and were allowed to spread freely. As can be seen from Table 3, only one solvent (dimethylsulfoxide) caused an increase in skin blood flow. The sites looked normal to the naked eye. In the second series of experiments, the neat solvents were applied in excess (1.5 ml/3.1 cm ) using a glass ring as a reservoir and attached with rubber bands to the forearm. Three different exposure times were used (1, 5, and 15 min) and, as can be seen from Table 3, the solvents varied greatly in their effects on skin blood flow. The most potent solvents were dimethylsulfoxide and trichloroethylene, while 15 min of exposure in excess to methyl ethyl ketone, propylene glycol, ethanol and water did not influence skin blood flow. [Pg.682]

As mentioned earlier, many of the tests that can be used to analyze green tape will not reveal the difference between the effects of the different plasticizers. For example, bending the tape around a known radius may show the extent of elongation before cracking (see section 5.1.4), but the tape may avoid cracking either by stretching of the "rubber bands or by permanent motion of the matrix. Further analysis would be needed to determine the reason for not cracking. [Pg.49]


See other pages where Rubber band effect is mentioned: [Pg.44]    [Pg.33]    [Pg.224]    [Pg.44]    [Pg.33]    [Pg.224]    [Pg.246]    [Pg.37]    [Pg.281]    [Pg.291]    [Pg.27]    [Pg.89]    [Pg.218]    [Pg.49]    [Pg.207]    [Pg.58]    [Pg.52]    [Pg.139]    [Pg.256]    [Pg.351]    [Pg.701]    [Pg.13]    [Pg.748]    [Pg.11]    [Pg.71]    [Pg.1093]    [Pg.414]    [Pg.234]    [Pg.166]    [Pg.141]    [Pg.826]    [Pg.456]    [Pg.456]   
See also in sourсe #XX -- [ Pg.224 ]




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