aluminum foams are a novel branch of advanced materials with superior properties. sandwich structures with aluminum foam core are good energy absorbers. in this paper, mechanical properties and energy absorption of aluminum foam sandwich panels subjected to quasi-static perforation tests with conical-nosed indenter were investigated experimentally. for this purpose sandwich panels consisting of...

Abstract. We consider a multigravity approach to spacetime foam. As an application we give indications on the computation of the cosmological constant, considered as an eigenvalue of a Sturm-Liouville problem. A variational approach with Gaussian trial wave functionals is used as a method to study such a problem. We approximate the equation to one loop in a Schwarzschild background and a zeta f...

the brass tubes with foam cores of alsi7sic3, alsi7sic3fe1 and alsi7sic3fe3 were produced as the crush-boxes with circle and square cross-section. then axial compressive behavior and energy absorption capability of the foam-filled tubes were investigated during the quasi-static progressive plastic buckling. the uniaxial compressive stress–strain curves of the foam-filled brass tubes exhibited t...

evaluating drainage systems, exploring their strengths and weaknesses, provides a comprehensive perspective to designers and organizers for optimum design and implementation of guidelines for the future. this study was conducted at an experimental site consisting of three plots on a subsurface drainage network under operation in behshahr, a coastal region in northern iran. to evaluate system pe...

[1] Soil water dynamics and drainage are key abiotic factors controlling losses of atmospherically deposited N in Southern California. In this paper soil N leaching and trace gaseous emissions simulated by the DAYCENT biogeochemical model using its original semi‐dynamic water flow module were compared to that coupled with a finite element transient water flow module (HYDRUS), for two mixed coni...

The relation between the sodium adsorption ratio (SAR) and pHc derived here predicts SAR of the drainage water (SARdw) better than existing empirical equations. Inaccuracies in SAR estimates from the new relationship can be anticipated by the extent to which the derived conditions are valid. Empirical equations provide no understanding of why they are sometimes inaccurate. Due to the relative i...

foam injection is widely applied in amounts of fields to drilling, production, and formation protection. sometimes, the application result is disappointing, which is caused by the failure of bubble generation in foam flooding. therefore, it is necessary to seek ways for improving the performance of foam injection. an increased disturbance to the stratum, like the vibration caused by a seismic o...