Interactions between lead and different binders
The present study describes the interactions between lead nitrate, representative of soluble lead compounds, and seven cements based on either ordinary Portland cement (OPC) or ground-granulated blast furnace slag (GGBFS). Suspensions of cements contaminated by lead nitrate were investigated by means of electrical conductivity, powder X-ray diffraction, Fourier Transform-infrared spectrometry, scanning electron microscopy, inductively coupled plasma-optic emission spectroscopy, and ionic chromatography. Pastes cast with these contaminated cements were submitted to leaching tests. The presence of fly ash was not favourable toward lead fixation and the best retention of lead was obtained with GGBFS-based cements. The most efficient binder was SPINOR, an ultrafine GGBFS-based cement.
Abstract : JAYCOR determined that much of the pressure trace detail from the M-198 155mm howitzer with the M203 charge could be understood in terms of gas dynamics and the gun and ground geometry. The objective was to determine the feasibility of simulating the far field muzzle blast and to interpret the field data already taken. A lung model was also developed which gives a way of comparing various pressure traces in terms of the internal dynamics. The agreement seen between measured and predicted pressure traces is repeated in the lung response. A bio- mechanical workshop was also held in Albuquerque, New Mexico on lung modeling. (Author)