AIMS To investigate whether twinning occurs more frequently in residents in the vicinity of a toxic waste incinerator (TWI). METHODS Within a longitudinal environmental study that addressed child health second grade school children and their parents were recruited. The proportion of twinning in the TWI region was compared with two comparison areas. In a second confirmatory investigation, birt...

A comprehensive theory of quasi-phase-matched (QPM) three-wave interactions in twinned plates of q3m semiconductors is developed. The 180* phase change required by QPM is studied by treating the nonlinear polarization as a bilinear form in the applied electric field and decomposing it into invariant and sign changing parts under a 2-fold rotation of an arbitrary crystal lattice. A new 3 X 3 mat...

The excellent cryogenic tensile properties of the CrMnFeCoNi alloy are generally caused by deformation twinning, which is difficult to achieve at room temperature because of insufficient stress for twinning. Here, we induced twinning at room temperature to improve the cryogenic tensile properties of the CrMnFeCoNi alloy. Considering grain size effects on the critical stress for twinning, twins ...

The Landau potential for multivariant displacive phase transformations (PTs) is derived for the most general case of large rotations, elastic and transformational strains, as well as nonlinear and different elastic properties of phases. The method of repetitive superposition of large strains is extended for PTs and is utilized in the finite-element method approach for solution of corresponding ...

Recent Bauschinger-type tests conducted on a twinning-induced plasticity (TWIP) steel highlights the important contribution of internal stresses to work hardening [1]. Along this line we present Bauschinger experiments in a Fe-22Mn wt.%-0.6C wt.% TWIP steel. The mechanical behaviour upon load reversal shows transient and permanent softening effects. Determination of the internal stress from the...

We report transmission electron microscope observations that provide evidence of deformation twinning in plastically deformed nanocrystalline aluminum. The presence of these twins is directly related to the nanocrystalline structure, because they are not observed in coarse-grained pure aluminum. We propose a dislocation-based model to explain the preference for deformation twins and stacking fa...

OBJECTIVE To assess the evidence of an association between periconceptional folic acid (FA) supplementation or fortification of foods with FA and the risk of twinning, using the Food Standards Australia New Zealand (FSANZ) framework for assessing evidence when substantiating nutrition, health and related claims on foods. DATA SOURCES The Cochrane Library Database, MEDLINE, MEDLINE in Process,...

Tetartohedral crystal twinning is discussed as a particular case of (pseudo)merohedral twinning when the number of twinned domains is four. Tetartohedrally twinned crystals often possess pseudosymmetry, with the rotational part of the pseudosymmetry operators coinciding with the twinning operators. Tetartohedrally twinned structures from the literature are reviewed and the recent structure dete...