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Porosity pockets

B An individual pocket of porosity shall not exceed the lesser of Ttt /3 or Vh in in its greatest dimension. The total area of porosity projected radially through the weld shall not exceed an area equivalent to 3 times the area of a single npaximum pocket allowable in any square inch (645 mnr) of projected weld area. [Pg.1007]

Porosity and low density because of the presence of air pockets or cavities due to occluded air. [Pg.165]

Polymerized [2]rotaxanes were claimed as good chemical vapour sensors [75]. In thin film form they were sensible to phenol vapours as well as to other H-bond donors such as p-nitrophenol or 2,2,2-trifluoroethanol. The observed phenomena was reversible and resulted in fluorescence quenching accompanied by a slight bathochromic shift. It was also found that the polymers were apt to metal bonding due to the presence of the tetrahedral pockets. This fact manifested itself in the appearance of an additional absorption band. The sensitivity of a given polymer thin film was proportional to the film porosity defined by steric properties of the R-substituant. The studies and applications of these molecules are just at the beginning. [Pg.641]

AM joints must be continuous solid welded. All welds must be smooth with no porosity holes, high spots, lumps, or pockets. Grinding is required to eliminate porosity, sharp edges, and high spots. [Pg.306]

Any water-soluble additive is liable to be dissolved and leached out from a laminate over a period of time when exposed to wet environments, and if the additive is a particulate soUd, dispersed in the resin, the result can be widespread porosity. Before the additive is washed out altogether, the trapped pockets of additive solution constitute osmotic pressure sites, which induce microcracks in the matrix. Figure 2.8 shows a cross-section through a unidirectional glass epoxy laminate, in which the dissolving of residual unused dicyandiamide hardener by a hot, wet atmosphere caused porosity and osmotic cracks. Prolonged exposure at 100°C caused fragmentation of the laminate [15]. [Pg.53]

Geophysical method Ground water exploration Water quality Porosity Permeability Temperature Flow rate and/or direction Buried channel Clay pockets in limestone Sand and gravel Basic igneous dykes... [Pg.47]

A h, cylindrical cells 0.1—10 A h and button cells 0.04-1.75 A h. The energy density of sintered plate cells is considerably better than their pocket plate counterparts because the electrodes are closer together, and with the high porosity of the plates there is also more active material per unit volume with a 100 A h cell... [Pg.265]

The polymer matrix can be specifically tailored to meet the requirements of the application or to enhance the stability of the specific enzyme to be immobilized. For instance, the porosity of poljmrethane foams can be influenced by the amount of surfactant added to the mixture prior to polymerization. Formation of gas as polyurethane cures causes pockets of air to form within the foam. Varying the concentration of surfactants added to promote porosity enables pore size to be varied. This can impact the ability to pass solutions through the polymers as well as their optical density for sensing applications. [Pg.2159]


See other pages where Porosity pockets is mentioned: [Pg.149]    [Pg.95]    [Pg.275]    [Pg.235]    [Pg.307]    [Pg.184]    [Pg.165]    [Pg.91]    [Pg.573]    [Pg.64]    [Pg.2794]    [Pg.46]    [Pg.1900]    [Pg.1901]    [Pg.167]    [Pg.1006]    [Pg.1346]    [Pg.184]    [Pg.70]    [Pg.92]    [Pg.433]    [Pg.565]    [Pg.429]    [Pg.93]    [Pg.311]    [Pg.251]    [Pg.181]    [Pg.138]    [Pg.260]    [Pg.553]    [Pg.283]    [Pg.556]    [Pg.556]    [Pg.570]    [Pg.170]    [Pg.740]    [Pg.310]   


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