In this study electrical discharge process was used to increase surface wear resistance of pure aluminum. Pulse-on-time and pulse current were considered as input parameters of the electrical discharge process. Experimental results reveal that the electrical discharge process is a successful method for improving the surface wear resistance of aluminum, so that this method has greatly increased ...

This study has analysed Li isotopes ratios from well-studied soil and pore water profiles Iceland that have the same parent material but experienced different degrees of chemical weathering. Thus, least to most weathered, we vitrosols (V), gleyic andosols (GA), brown (BA), Histosols (H) Histic Andosols (HA). Although weathered H HA soils highest content in clay-sized material, they fractionated...

the concepts of democracy have been around for centuries in different fields of human sciences. however, in most of these fields the idealistic and far-fetched features attributed to democracy have not been manipulated yet. it should be mentioned that there have been only a few serious attempts to find proper go-between elements, which could make such a concept as comprehensible and tangible as...

While grassland restorations have gained recent popularity throughout the United States, few restorations have been initiated on the highly weathered soils of the Mid-Atlantic Coastal Plain; thus potential soil response to grassland management practices, such as prescribed burning, are not clearly understood in this region. The objective of this study was to evaluate the impacts of prescribed b...

We used the Hedley sequential fractionation scheme to assess phosphorus (P) chemistry of a strongly weathered soil from a humid lowland forest in Panama. Our analyses were part of a factorial experiment of nitrogen, P, and potassium addition, with nutrients added annually, i.e. a chronic input. The aim was to examine changes in soil P chemistry with 7 years of nutrient addition for soils collec...

Increased resistance of weathered cotton cellulose to microbial breakdown has been shown to be the result of development of resistance to the action of fungal cellulases. Photochemical activity during weathering exposure transforms the cellulose into an altered substrate that prevents access of the enzymes to susceptible sites of the cellulose molecule. It is postulated that the altered substra...

Most studies of active aeolian processes on Mars have focused on dust [1], i.e., particles -1 [tm in diameter that are transported in suspension by wind. The presence of sand dunes on Mars [2-8] indicates that larger grains ( >60 _tm, transported primarily in saltation) are also present. Although indirect evidence suggests that some dunes may be active [9], definitive evidence is lacking. Nonet...

Outlined is a new approach to the problem of surfacing particle-based fluid simulations. The key idea is to construct a surface that is as smooth as possible while remaining faithful to the particle locations. We describe a mesh-based algorithm that expresses the surface in terms of a constrained optimization problem. Our algorithm incorporates a secondary contribution in Marching Tiles, a gene...