Application of ICP-MS radionuclide analysis to “Real World” samples of department of Energy radioactive waste

Germanium spectrometers must be operated at liquid nitrogen temperatures. Other detectors operate better when cooled. Many applications, because of hostile environments, inaccessibility, remote location, long duration, etc., are compromised, or totally precluded, by the requirement for liquid nitrogen. A Stirling cycle refrigerator based on a linear motor design, which is acoustically and vibrationally quiet, does not require secondary cooling, and operates unattended for years, is under development. System design and specifications are presented. Applications to cooled laser monitoring equipment. SQUID-based detection systems, environmental cleanup and monitoring, medical diagnostics, non-destructive testing systems, communication equipment, computer electronics, and imaging systems are discussed.     

Isoperimetric domains of large volume in homogeneous three-manifolds

Given a non-compact, simply connected homogeneous three-manifold X   and a sequence _{Ωn}n${\{{\Omega }_n\}}_n$ of isoperimetric domains in X   with volumes tending to infinity, we prove that, as n→∞$n\to \infty$:

(1)

The radii of the _Ωn${\Omega }_n$ tend to infinity.     

Classification of doubly-periodic minimal surfaces of genus zero

We prove that if the quotient surface of a properly embedded doubly–periodic minimal surface in ℝ³ has genus zero, then the surface is one of the classical Scherk examples. Oblatum 30-IX-1998 & 18-II-2000?Published online: 30 October 2000     

Limits of minimal surfaces and Scherk's Fifth Surface

Communicated by J. C. C. Nitsche     

The structure of singly-periodic minimal surfaces

The research described in this paper was supported by research grant DE-FG02-86ER250125 of the Applied Mathematical Science subprogram of Office of Energy Research, U.S. Department of Energy, and National Science Foundation grants DMS-8611574 and DMS-8802858