Core-shell nanoparticles consisting of silica as core and surface-grafted poly(dimethylsiloxane) (PDMS) as shell with different diameters were prepared and used as heterogeneous nucleation agents to obtain CO2-blown poly(methyl methacrylate) (PMMA) nanocomposite foams. PDMS was selected as the shell material as it possesses a low surface energy and high CO2-philicity. The successful synthesis o...

Herein, we designed and synthesized for the first time a series of 3D dendritic heterojunction arrays on Ni foam substrates, with NiCo2S4 nanowires as cores and NiCo2O4, NiO, Co3O4, and MnO2 nanowires as branches, and studied systematically their electrochemical performance in comparison with their counterparts in core/shell structure. Attributed to the following reasons: (1) both core and bran...

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...

Metals foams are attracting great interest in aerospace, automotive and military fields. Particularly, the closed-cells aluminum characterized by peculiar properties, such as low specific weight coupled with high energy absorption capacity, stiffness strength reduced thermal electrical conductivity. For above reasons, can be effectively used core of sandwich structures, replacing traditional ho...

The high strain rate behavior of two cellular materials was investigated using a quasi-static loading stage and a Kolsky bar apparatus. The yield stress of these core materials under dynamic loading was found higher than in quasi-static loading. However, the plateau stress after yielding is not so sensitive to strain rate. For Aluminum foam materials, the deformation was more localized for quas...

Plaque rupture underlies most myocardial infarctions. Plaques vulnerable to rupture have thin fibrous caps, an excess of macrophages over vascular smooth muscle cells, large lipid cores, and depletion of collagen and other matrix proteins form the cap and lipid core. Production of matrix metalloproteinases from macrophages is prominent in human plaques, and studies in genetically modified mice ...

in many processes polymeric foams can be produced by using chemical or physical blowing agents. in this work for polyethylene foam production, the chemical blowing agents and compression moulding process were employed. at first, by using dsc diagram of two polyethylene grades, a suitable polyethylene grade was selected for foam production and then we discuss about blowing agent critical percent...

The present work was aimed to examine the effects of incorporation of each of two different types of nanoclay, i.e. Cloisite Na+ and Cloisite 30B, into PVA foam on cellular morphology and water absorption capacity. Foam samples containing 0.0-10.0 wt% of each of the two types of nanoclay alone were prepared using mechanical foaming. Accordingly, PVA/organoclay/water suspensions were prepare...

Closed cell aluminum foams have received much recent attention as energy absorbing materials on account of their ability to undergo extensive deformation at a relatively low stress called the plateau stress. Several studies describe the improvements in energy absorption to be obtained, relative to their empty counterparts, when foam filled tubes are crushed either quasi-statically or dynamicall...

This investigation presents the effect of various parameters on foam stability and its rheological properties. The underlying idea of this experiment is generating of drilling foam with uniform bubbles. The main problem of foam using is controlling its stability during field application. The most important parameters which cause Instability in foam are gravity drainage, gas diffusion and bu...