Glass foam tablets were produced from container glass bottles (CGB) using eggshell waste (ESW) and perlite (P) as foaming agent in different portions. The ground raw materials (CGB, ESW, P) homogenized pressed with hydraulic piston press machine at pressures (in the case of P containing 30 MPa ESW 15 MPa, 40 used).The obtained heat treated temperatures 800 °C, 900°C, 1000°C 1100°C, 600 700 °C 9...

Placebo controls are commonly used in clinical trials of investigational treatments because they have important advantages. In recent years, some have criticized the use of placebo-controlled trials when effective alternative therapy exists, regardless of the expected effect of the therapy. In part 1 of this paper, ethical arguments are addressed and the interpretive problems inherent in the us...