A chuck for angular offset woodturning including a first member adapted to be secured to a lathe, and a second member adapted to support a work piece and secured to the first member in such that the second member is oriented with respect to the first member between at least two configurations. For example, some fluid treatment assemblies and elements may be used to remove one or more substances from the fluid and may then function as separators, including filters and concentrators. A shell may encapsulate a nanoparticle core, and the shell may include non-organic material and may be silica. A plurality of corner masonry article and plurality of alternative corner masonry articles similar to the plurality of masonry articles permit assembly of a portion of a corner section of the wall.