Strain transfer

The picture tliat emerges is of crystals embedded in and linked to a NXL phase that orients continuously with increased extension. Strains transferred to the crystals lead to two distinct modes of slip within the PILE crystals and to the orientation, fragmentation, and alignment of lamellae at progressively higher strains. 

From a mechanical point of view, a critical level of adhesion (chemical or physical) is required between TP and thermoset TS phases to insure stress and strain transfers and to favor ductile stretching of TP particles in the crack-bridging mechanism (Pearson, 1993 Hodgkin et al., 1998). 

Extrachromosomally mediated streptomycin resistance has been reported by many workers (see p. 386). Pseudomonas strains transferring streptomycin resistance transferred to the recipient strain the ability to produce phosphorylating enzyme [210]. 

Another example is the use of the solution casting technique to produce PVC composites with MWNTs, which have values of dT/dFf of 204 GPa. With Kevlar-functionalised MWNT-PVC composites, however, there is a substantial increase in dl7dFf to 300 GPa." These values are quite close to the maximum expected value of dlVdFf. " This indicates on very good stress-strain transfer between PVC and the Kevlar-coated nanotubes. Most importantly, the reinforcement was achieved at less than 2 wt% nanotube content, which a great advantage if we take into account the nanotube costs. 

Many of the uncertainties associated with the above tests arise from the model used to calculate the stress or strain transferred between the matrix and fibre. (Laser Raman or Fluorescence Spectroscopy) LRS is a technique for determining directly the strain in the fibre in analogy to an embedded strain gauge. The strain is probed by recording a Raman (or fluorescence) spectrum of the reinforcing fibre at increments of applied strain. The shift in the frequency at which a stress-sensitive peak occurs can be used to estimate the strain profile in fhe reinforcing fibre. The rate of strain development in the fibre can be used to assess the quality of the interface. Quantification still requires an appropriate stress-transfer model although a simple force-balance calculation can be used to estimate the interfacial shear stress. 

Laboratory studies of several strains have shown the great instabiUly of the ropy phenotype. Strains transferred to a medium without ethanol rapidly lose this properly. This result led to the comparison of ropy strains and their mutants. The presence of a plasmid distinguishes the strains. On this is a small plasmid with 5.5 kbp three coding genes have been identified by homology, one probably for repUcase, the second for a mobilization protein. 

TsaMris SA, RousaMs TC, Karabinis AI (2012) Confinement effects and strain transfer in reinforced concrete Jackets of different detailing for the strengthening of old-type concrete columns. In 15th world conference on earthquake engineering, 24—28 Sept 2012, Lisbon... 

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