The geographic mosaic theory of coevolution predicts 1) spatial variation in predatory structures as well as prey defensive traits, and 2) trait matching in some areas and trait mismatching in others mediated by gene flow. We examined gene flow and documented spatial variation in crushing resistance in the freshwater snails Mexipyrgus churinceanus, Mexithauma quadripaludium, Nymphophilus minckl...

Particle crushing dominates the deformation behaviour of granular materials under significantly high compressive and shear stress. A proposed constitutive model has been verified to predict crushing behaviour of granular materials with different crushability and adopted one kind of reference crushing stress. It is noted that no positive dilatancy of granular material in triaxial test occurs onc...

To maximize the controllable energy absorption of corrugation troughs as observed in the single sided corrugated (SSC) tube, we proposed and tested a new structure design, i.e., double-sided corrugated (DSC) tube made of Al 6060-T6 aluminum alloy or CF1263 carbon/epoxy composite. Finite element models were developed to test the mechanical advantage of the DSC tube in comparison with both SSC an...

A novel energy-saving hydrometallurgical recovery process for copper from electronic scrap employing the Cu(I)-ammine complex has been presented on the basis of a thermodynamic consideration. In order to experimentally explore the feasibility of the leaching stage in this process, the copper leaching behavior from a printed circuit board (PCB) in ammoniacal alkaline solutions has been investiga...

car body lightening and crashworthiness are two important objectives of car design. due to their excellent performance, composite materials are extensively used in the car industries. in addition, reducing the weight of vehicle is effective in decreasing the fuel consumption. hat shape energy absorber is used in car’s doors for side impact protection. the aim of these numerical models and exper...

The compaction and re-crushing characteristics of crushed gangue are important factors which affect the quality effectiveness filling quarry. To study particles, continuous grading intermittent two different structures were designed to bulk particle size distribution. By conducting a side-limited uniaxial compression test on gangue, deformation parameters samples under axial pressure conditions...

In this article, crashworthiness performance and crushing behavior of tapered structures with four internal reinforcing plates under axial and oblique dynamic loadings have been investigated. These structures have a tapered form with five cross sections of square, hexagonal, octagonal, decagon and circular shape. In the first step, finite element simulations performed in LS-DYNA were validated ...

In the present article, a numerical study is performed to investigate the crushing behavior of cylindrical and conical corrugated composite tubes. Different aluminum foams are applied to the proposed structures in order to offer an excellent energy absorption capacity. The crushing behavior of tubes are evaluated in terms of two parameters: SEA (specific energy absorption) and CFE (crush force ...

Polyakov et al. (1995) showed errors in dose estimation as a function of grain size for enamel grains given beta irradiation after crushing. We tested the effect of gamma irradiation applied to the specimens before and after crushing. We confirmed Polyakov's observations and found that post-crushing irradiation altered the slope of the dose-response curve of the hydroxyapatite signal and produc...