In this project we measure the neutron capture cross section of ²⁰⁸Pb. We began by calibrating our silicon detector with ²⁰⁴Tl. Two experiments were then performed, the first in December of 1999 and the second in March of 2000. Both experiments were performed in the nuclear reactor of the Radiation...
We present a decade-long (1981–1990) high-resolution (subseasonal) record of Pb and Cd concentrations and Pb isotopic composition in a series of 119 snow samples from a 6-m snow pit at Summit, Greenland. Both metals show order of magnitude seasonal variability, with maxima in spring of every year, coinciding with sulfate...
Pb(Zr₀.₅₂Ti₀.₄₈)O₃ (PZT) thin films are of interest for their large dielectric permittivity, ferroelectric, and piezoelectric properties. The material has been widely studied for use in high frequency transducers, multi-layered capacitors, and ferroelectric random access memory. Copper foils are an inexpensive, flexible substrate with a low resistivity which makes them ideal...
Pb-isotope data on ore galenas from the West Shropshire orefield show a significant spread of ²⁰⁶pb/²⁰⁴pb values, with minor variation in ²⁰⁷Pb/²⁰⁴Pb and ²⁰⁸Pb/²⁰⁴Pb ratios. These indicate that lead was derived from multiple sources, some of them uranium-enriched and incompletely mixed prior to ore deposition. Four possible mineralizing agents are...
Inclusive polarized proton-nucleus scattering at 290 and 500 MeV was
performed using a ²⁰⁸Pb(51 mg/cm²) target. A broad range (0-250 MeV) of
excitation energy has been studied over the 4° - 27° angular range. The measured analyzing power and cross section of the continuum are compared with
the recent DWIA...
The piezoelectric fatigue behavior of Pb-free ceramics based on solid solutions of Bi(Zn₀.₅Ti₀.₅)O₃-(Bi₀.5K₀.₅)TiO₃-(Bi₀.₅Na₀.₅)TiO₃ was characterized at 50 kV/cm after 10⁶ bipolar cycles. Ferroelectric compositions containing 2.5% Bi(Zn₀.₅Ti₀.₅)O₃ exhibited only minor losses in maximum strain (~10%). In compositions with 5% Bi(Zn₀.₅Ti₀.₅)O₃ that exhibit large electric field-induced strains, the electromechanical strain actually...
The yields of over 200 projectile-like fragments (PLFs) and target-like fragments (TLFs) from the interaction of (E[subscript]c.m.=450 MeV) Xe¹³⁶ with a thick target of Pb²⁰⁸ were measured using Gammasphere and off-line γ-ray spectroscopy, giving a comprehensive picture of the production cross sections in this reaction. The measured yields were compared...
Pb(Zr,Ti)O₃ (PZT) is a very attractive material for use in piezoelectric-based microelectromechanical systems (MEMS) due to its high piezoelectric coefficients and ability for large displacements with relatively low applied fields (as compared to electrostatic-based MEMS). The piezoelectric effect is strongly anisotropic, thus it is very desirable to control the crystallographic...
Piezoelectric materials convert mechanical strain into a dielectric displacement, as well as the converse, allowing these materials to be used as sensors, actuators, and transducers. Currently, lead zirconate titanate (PZT) is the primary material used in these applications. Due to environmental toxicity and safety concerns associated with Pb, development of...