Effect of aspect ratio on strain sensing capacity of carbon fiber reinforced cement composites

The electrical resistivity of carbon fiber reinforced cement composites (CFRCCs) has been widely studied, because of their utility as multifunctional materials. The percolation phenomenon has also been reported and modeled when the electrical behavior of those materials had to be characterized. Amongst the multiple applications of multifunctional cement composites the ability of a CFRCC to act as a strain sensor is attractive. This paper provides experimental data relating self-sensing function and percolation threshold, and studying the effect of fiber aspect ratio on both phenomena. Higher fiber slenderness permitted percolation at lower carbon fiber addition, affected mechanical properties and improved strain-sensing sensitivity of CFRCC, which was also improved if percolation had not been achieved.

Controlled rippling of graphene via irradiation and applied strain modify its mechanical properties: a nanoindentation simulation study

Ripples, present in free standing graphene, have an important influence in the mechanical behavior of this two-dimensional material. In this work we show through nanoindentation simulations, how out-of-plane displacements can be modified by strain resulting in softening of the membrane under compression and stiffening under tension. Irradiation also induces changes in the mechanical properties of graphene. Interestingly, compressed samples, irradiated at low doses are stiffened by the irradiation while samples under tensile strain do not show significant changes in their mechanical properties. These simulations indicate that vacancies, produced by the energetic ions, cannot be the ones directly responsible for this behavior. However, changes in roughness induced by the momentum transferred from the energetic ions to the membrane, can explain these differences. These results provide an alternative explanation to recent experimental observations of stiffening of graphene under low dose irradiation, as well as paths to tailor the mechanical properties of this material via applied strain and irradiation.

Forecasting migration between the EU, V4 and Eastern Europe. Impact of visa abolition. OSW Report, July 2014

This book is the result of one year of solid work among a multinational research team assembled from seven states (Poland, Czechia, Hungary, Slovakia, Ukraine, Belarus and Moldova). It aims at a detailed analysis of migration patterns and migration forecasts from Ukraine, Belarus and Moldova to the EU/V4. In particular, the nexus between EU visa policy and migration dynamics as well as the impact of economic, political and institutional factors on migration from Eastern Europe have been investigated. The importance of migration policy must be stressed here. Together with demand for the foreign labour force (labour market needs, level of wages, existing work opportunities) and migration networks (including ethnic links), migration policy has a powerful influence on the scale, directions and characteristics of human flows.

Strain-induced structural instability in FeRh

We perform density functional calculations to investigate the structure of the intermetallic alloy FeRh under epitaxial strain. Bulk FeRh exhibits a metamagnetic transition from a low-temperature antiferromagnetic (AFM) phase to a ferromagnetic phase at 350 K, and its strain dependence is of interest for tuning the transition temperature to the room-temperature operating conditions of typical memory devices. We find an unusually strong dependence of the structural energetics on the choice of exchange-correlation functional, with the usual local density approximation yielding the wrong ground-state structure, and generalized gradient (GGA) extensions being in better agreement with the bulk experimental structure. Using the GGA we show the existence of a metastable face-centered-cubic-like AFM structure that is reached from the ground-state body-centered-cubic-like AFM structure by following the epitaxial Bain path. We show that the behavior is well described using nonlinear elasticity theory, which captures the softening and eventual sign change of the orthorhombic shear modulus under compressive strain, consistent with this structural instability. Finally, we predict the existence of an additional unit-cell-doubling lattice instability, which should be observable at low temperature.

The true stress-strain properties of brittle materials to 5000° F : final report.

"5081-1190-XIV ; July 28, 1961."

Strain gage techniques : fundamentals (July 8-12, 1958), applications (July 14-18, 1958) : lectures and laboratory exercises /

Includes bibliographies.

Buckling of uniformly compressed steel plates in the strain-hardening range.

"This work has been carried out as part of an investigation sponsored jointly by the Welding Research Council and the Department of the Navy with funds furnished by the following: American Institute of Steel Construction [and others]."

Strain gage techniques: fundamentals (Aug. 9-13, 1954), applications (Aug. 16-20, 1954)

Includes bibliographies.

"Life cycling" test on several strain gage pressure transducers.

Includes bibliography.

Survival of the BUK vaccinal strain of Aujeszky's disease virus in aerosol form,

Mode of access: Internet.

Heat stress, heat strain, and productivity in Washington State tree fruit harvesters

Thesis (Master's)--University of Washington, 2016-06