Slip during tension testing of Mg-3A1-1Zn sheet

The activation of slip and twinning deformation modes in Mg-3Al-1Zn alloy was investigated by means of both in-situ and ex-situ methods at ambient temperature using electron back scattering diffraction (EBSD). The results confirm the importance of non-basal slip and c-axis compression double twinning. During tensile deformation of rolled sheet, 63% of the observed slip traces were ascribed to prismatic slip, 33% to basal slip and 4% to <c+a> slip. Prismatic slip was frequently observed in grain interiors. The density of twinning was quantified in samples tested along transverse, extrusion and rolling directions at failure. The values in the range of 0.02-0.18 twins per square micron were found depending on sample orientation. The results show the effect of twinning on failure.

Shake rattle and roll: a journey with Parkinson's

This is the journey of a man suffering from Parkinson's disease. Ross Collins tells of his past twelve years' experiences of living with Parkinson's. Before, he had a steady job with Victoria Police, with promising future prospects; and was happily married with two young children. The disease struck him at an early age, changing his life and setting him on a different course. His outlook on life has changed, and his decision-making influenced; as well, his relationships with his family affected. He feels normal only when he is shaking, rattling and rolling along on his Harley. His wish for a cure leads him to pin his hopes on faith healing by the 'miracle man', in Brazil. The first two visits did not seem to have done anything to improve his physical condition. Ross is returning to Brazil for the third time, hoping against hope that his condition could be improved by a miracle healing. This documentary gives an intimate look into the life of a Parkinson's disease sufferer and that of his family. Includes al.

Necking and failure at low strains in a coarse-grained wrought Mg alloy

Tensile testing of rolled AZ31 alloy with a mean grain size of 80 μm reveals localization and failure prior to diffuse necking. Optical microscopy reveals that failure is caused by voids that have formed within twins. A simple localization criterion is proposed that captures the role of grain size in the effect. Such early failure is only predicted for coarse grain sizes, in line with observation.

Fine grained AZ31 produced by conventional thermo-mechanical processing

The magnesium alloy AZ31 was processed by severe hot rolling and annealing. This processing was optimised to produce recrystallised grain sizes as small as 2.2 μm. The texture of the processed plate was similar to that of the as-received material, with a strong basal alignment in the normal direction. Tensile testing of the fine grained material showed an increase in the strength and elongation compared to the as-received plate. It is  concluded that the improved mechanical properties of the fine grained material results from a refinement in the grain size and the elimination of shear bands that pre-exist in the as-received material.

Correlation between the deformation and post-deformation softening behaviours in hot worked Austenite

The relation between the deformation and post-deformation softening behaviours of austenite is examined in a 304 stainless steel. This correlation has been exploited in the modelling of hot rolling and it is argued here that the key to this understanding lies in the deformation structure. The latter is characterized in the present work by the fraction of dynamic recrystallization. The value of this fraction at the peak in the flow stress curve is found to decrease with increasing stress (i.e. with decreasing temperature and increasing strain rate). By contrast, the fraction of dynamic  recrystallization at the strain corresponding to the point where  post-deformation softening becomes strain independent is found to be constant. These observations are used to explain the nature of the important difference between the flow curve peak and the onset of strain independent post-deformation softening.

Barriers to cross-fertilization between populations of a widely dispersed Polychaete species are unlikely to have arisen through gametic compatibility arms-races

Although there are theoretical reasons to suspect that gametic incompatibility may develop readily among populations of broadcast spawning marine invertebrates, there have been very few studies documenting geographic patterns of interpopulation incompatibility for any species. To address this we determined how successfully individuals of the intertidal serpulid polychaete, Galeolaria caespitosa, can cross-fertilize within and among populations from across temperate Australia. Fertilization assays revealed asymmetrical differences between very distantly located populations from different coasts, with near-complete incompatibility between eggs from Sydney with sperm from Adelaide, but the reverse cross (Adelaide eggs, Sydney sperm) was reasonably compatible. Although that pattern was congruent with a clear difference in Cytochrome B sequences between worms on the south and east coasts of Australia, we also detected some indication of interpopulation incompatibility within the genetic grouping on east coast, between two populations separated by only 220 km. We then assessed whether commonly proposed gametic compatibility arms-races could account for these patterns. Our results suggest reduced gametic compatibility may reduce a female's maximum fertilization potential, resulting in a cost to this potential mechanism for reducing polyspermy. Consequently, the apparently rapid development of reproductive barriers here seems unlikely to have been driven by arms-races involving sexual conflict over fertilization rate.

The effect of prestrain and bake hardening on the low-cycle fatigue properties of TRIP steel

The scope of this study was to examine the effects of plane strain prestrain, induced via cold-rolling, and subsequent automotive paint bake hardening cycle on both tensile and fatigue properties of a hot rolled TRIP780 multiphase steel. Strain-life data has been generated for as-received (0% prestrain), 10% and 20% prestrained samples, in both baked and unbaked conditions. Cold rolling  increased the number of strain reversals to failure at high cyclic strain amplitudes with no effect at low strain amplitudes. Bake hardening increased the number of reversals to failure at high cyclic strain amplitudes. The prestrained material exhibited partial cyclic softening, with some residual strength increase. The residual strength increase was attributed to the austenite to martensite transformation that occurred during the prestraining process.

Diversions

The article highlights various books that integrates mathematics in activities and solving problems. The author stated that the novel "The Dice Man" of Luke Rhinehart describes a person who decides to use rolling a dice to make important decisions. Meanwhile, the "Casino Royale" of Ian Fleming highlights the character as an extremely experienced gambler. On the other hand, the "Lieutenant Hornblower" of C. S. Forester highlights the character who support himself by playing whist.

An intelligent energy management model for a parallel hybrid vehicle under combined loads

To exploit the benefits offered by parallel HEVs, an intelligent energy management model is developed and evaluated in this paper. Despite most existing works, the developed model incorporates combined wind/drag, slope, rolling, and accessories loads to minimise the fuel consumption under varying driving conditions. A slope prediction unit is also employed. The engine and the electric motor can output power simultaneously under a heavy-load or a slopped road condition. Two simulation were conducted namely slopped-windy-prediction and slopped-windy-prediction-hybrid. The results indicate that the vehicle speed and acceleration is smoother where the hybrid component was included. The average fuel consumption for the first and second simulations were 7.94 and 7.46 liter/100 km, respectively.

Effect of grain size on deformation twinning behaviour of high MN steel

The effect of grain size on the mechanical properties and deformation twinning behaviour in high manganese steel was investigated. In order to generate different grain sizes, the samples were subjected to hot rolling, cold rolling and annealing. Room temperature tensile testing of the steel with different grain sizes (5-50 µm) indicated the occurrence of twinning induced plasticity (TWIP) in all the samples. Also, changes in work-hardening behaviour accompanied changes in the grain size. The results are discussed in terms of the enhanced sensitivity of twinning to the grain size.

The microstructure evolution and mechanical properties of cryorolled Al alloys

A solutionized Al2024 alloy was subjected to rolling at liquid nitrogen temperature (cryorolling) resulting in an ultra-fine stmcture. The material was also subjected to recovery annealing at 160°C. The ultrafine structured material demonstrated increased strength but very low ductility. The uniform elongation of the material after recovery annealing increased without any sacrifice of strength.

Fish assemblage response to rehabilitation of a sand-slugged lowland river

The impact of excessive sediment supply on river channels has been  described in many areas of the world. Sediment deposition disturbance alters habitat  structure by decreasing channel depth, changing substrate composition and burying woody debris. River rehabilitation is occurring worldwide, but information is scant on fish assemblage responses to rehabilitation in sedimentdisturbed lowland rivers. Sediment removal and large woody debris (LWD) replacement  were used to experimentally rehabilitate habitat along a 1500m stretch of the Glenelg River in western Victoria, Australia. Using an asymmetrical before-after control-impact (BACI) design, fish were captured before and after the reach was rehabilitated, from two control reaches and from a ‘higher quality’ reference reach. After two years post-rehabilitation monitoring, the fish assemblage at the rehabilitated reach did not differ from control reaches. Temporal changes in taxa richness and the abundance of Philypnodon grandiceps, Nannoperca spp. and three angling taxa occurred after rehabilitation (winter 2003) compared with the before period (winter 2002), but these effects did not differ between rehabilitated and control locations. Highest taxa richness and abundances occurred at the reference location. High salinity coincided with the timing of rehabilitation works, associated with low river discharges due to drought. The negative effects of other large-scale disturbances may have impaired the effectiveness of reachscale rehabilitation or the effects of rehabilitation may take longer than two years to develop in a lowland river subjected to multiple environmental disturbances.

Electron back scattered diffraction (EBSD) characterization of warm rolled and accumulative roll bonding (ARB) processed ferrite

An interstitial free (IF) steel was severely deformed using accumulative roll bonding (ARB) process and warm rolling. The maximum equivalent strains for ARB and warm rolling were 4.8 and 4.0, respectively. The microstructure and micro-texture were studied using optical microscopy and scanning electron microscopy equipped with electron back scattered diffraction (EBSD). The grain size and misorientation obtained by both methods are in the same range. The microstructure in the ARB samples after 6 cycles is homogeneous, although a grain size gradient is observed at the layers close to the surface. The through thickness texture gradient in the ARB samples is different from the warm rolled samples. While a shear texture (⟨110⟩//rolling plane normal direction (ND)) at the surface and rolling texture at the center region is developed in the ARB  samples, the overall texture is weak. The warm rolled samples display a sharp rolling texture through the thickness with increasing the sharpness toward the center. These differences are attributed to the fact that the central region of ARB strip is comprised of material that was once at the surface. The ARB process  can suppress the formation of shear bands which are conventional at warm rolled IF steels. EBSD study on the sample with 6th cycle of ARB following the annealing at 750 ◦C verified a texture gradient through the thickness of the sheet. The shear orientations at the surface and at the quarter thickness layers can be identified even after annealing. The overall weak texture and existence of shear orientations make ARB processed samples unfavorable for sheet metal forming in compare with warm rolled samples.

understanding Fiji's declining foreign reserves position

This article examines the volatility in Fiji’s foreign reserves—in particular, whether shocks have an asymmetrical effect on volatility and whether shocks have a  persistent impact on volatility. In the pre-coup period (1975–86), shocks had a temporary effect on volatility; in the coup period (1987–2006), shocks had a more lasting impact. In the pre-coup period, negative shocks contributed more to  foreign reserves volatility than positive shocks; but in the period including the  coups, positive shocks increased the volatility of foreign reserves more than  negative shocks. The reasons for, and the policy implications of, this  asymmetrical behaviour are explored.

Clinical supervision and symmetrical communication : towards a critical practice of supervision

The central argument of the thesis is that the dominant modes of the supervision of teaching are in need of critique and reconstruction. From a critical perspective, supervision is viewed as a political and ideological process enacted through asymmetrical relations and structures of communication. It is underpinned by a discourse of technocratic rationality and control Clinical supervision, a currently popular model of teacher supervision, has (despite its emancipatory origins) been accommodated by the dominant ideology and is employed as a hegemonic mechanism of evaluation, control and even dismissal of teachers. However, historical analysis reveals that teachers have contested and resisted authoritarianism and centralized control in favour of developing more democratic and participatory forms of professional development. In these moves can be found a rationale for a reconstruction of the theory and practice of clinical supervision around the concepts of symmetrical communication and critical pedagogy. The researcher engaged in a self-reflective study with a group of supervisors and teachers in N.S.W. schools to explore the possibilities and limitations of a critical and counter-hegemonic practice of supervision. The outcomes, in the form of three case studies, are analysed in terms of a dialectic of reconstruction and maintenance of the status quo. The evidence reveals that some of the research participants sought to reconstruct their supervisory relationships in ways which challenged the bureaucratic structures of their workplace. Others, however, rejected the emancipatory possibilities and resolved to maintain their traditional hierarchical relationship.