Contraction stresses

Material Density (g/cm 1 Coating weight (kg/m ) 0-025 mm thickness Brinell hardness Ratio of contraction stresses in sprayed deposits 0-51 mm thick Compressive strength (stress to collapse) (MN/m )... 

ISO 14236 2000 Plastics pipes and fittings - Mechanical-joint compression fittings for use with polyethylene pressure pipes in water supply systems ISO 14616 1997 Plastics - Heatshrinkable films of polyethylene, ethylene copolymers and their mixtures - Determination of shrinkage stress and contraction stress ISO 14632 1998 Extruded sheets of polyethylene (PE-HD) - Requirements and test methods... 

The different behavior of the 100% excess sample is a result of the low elastic modulus and Tg. As the elastic modulus and Tg of the sample decrease, the deflections become more negative and contractive stresses begin to appear. 

Fig. 32. Dependence of mechanochemical contraction, stress and water permeability of a complex membrane consisting of poly-(methacrylic add) (PMAA) and poly(ethylene oxide) (PEO) on the molecular weight of PEO483. (1) Relative permeability to water,...

Contraction stresses that developed during solidification... 

This curling can be attributed to an internal stress arising in the plasma polymer during polymer deposition. It is important to recognize that the internal stress in the plasma polymer (in the as-polymerized state) is an expansive stress and that this is in marked contrast to what would be expected if the adsorbed monomer were polymerized at the surface of the substrate, which would create, with very few exceptions, contractive stress due to the contraction of volume on the polymerization of a monomer. 

Chorionic villus sampling Colposcopy Cytomegalovirus Endometrial biopsy Estriol excretion Fetal biophysical profile Fetal contraction stress test Fetal nonstress test Fetal scalp blood pH Fetoscopy... 

It is known that, in contrast to plastics, rubber chains break down only when they are fully stretched (Kinloch and Young, 1983 Kausch, 1987). An ultrasonic field creates high frequency extension-contraction stresses in crosslinked media. Therefore, the effects of rubber viscoelasticity have been incorporated into the description of dynamics of cavitation (Yashin and Isayev, 1999, 2000). The devulcanization of the rubber network can occur primarily around pulsating cavities due to the highest level of strain produced by the power ultrasound (Yashin and Isayev, 2000). 

The contractile apparatus in nonmuscle cells has many of the same proteins found in sarcomeres. Bundles of actin and myosin are known as stress fibers, which provide the cytoskeletal tension required for migration or contraction. Stress fibers are composed of bundles of actin filaments that are held... 

C.J. Kleverlaan, A.J. Feilzer, Polymerization shrinkage and contraction stress of dental resin composites, Dent. Mater. 21 (2005) 1150-1157. 

Like conventional composites, the polymerization reaction in polyacid-modified composite resins is associated with a contraction in the overall volume of the material and a corresponding contraction stress [13], Experiments showed that the values... 

H.V. Chen, K. Manhart, K.-H. Kunzelmann, R. Hickel, Polymerization contraction stress in hght-cured packable composite resins. Dent. Mater. 19 (2003) 597-602. 

The internal stresses in adhesive-bonded joints arise for two reasons. In the course of setting of the adhesive, its volmne decreases due to volatilization of solvents, polymerization or physical structurization. As a result of the adhesion interaction of the adhesive and the substrate, the film can contract only in thickness, which is why stresses that appear in it are parallel to the siuface. The film extends while contraction stresses appear in the substrates. Rapid growth of stresses, which tend to reduce the length of the film, begins from the moment the polymer loses yield. 

Contraction stresses develop when slab/environmental temperature decreases. Contraction tensile stresses should be defused otherwise, contraction cracks will develop. To avoid contraction stresses, adequately spaced contraction joints are provided. 

C.L. Davidson, A.J. de Gee, A. Feilzer, The competition between the composite-dentin bond strength and the polymerization contraction stress, / Dent. Res., 63, 1396-1399,... 

Based on the theory of bending mechanism, surfactants bound on the gel surface generate stress on the surface, because of anisotropic contraction. Stress cause strain on the surface of gel. 

Thermal Stress - Reduced width of the operating temperature band reduces thermal expansion and contraction stresses during cycling, thus maintaining geometric stability. 

Igarashi, T., Kondo, S., Kurokawa, M. (1979). Contractive stress of epoxy-resin during isothermal curing. Polymer, 20(3), 301-304. 

The shrinkage allowance s, which is to produce the calculated contraction stress is given by ... 

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