Thermophysical properties measurements performed for NASA

Thermoconductivity, specific heat, and density measurement test progra

On the Marginal Cost of Wastewater Services

The purpose of this paper is to analyze the marginal cost of municipal wastewater services. We begin by describing the nature of wastewater services. This is of importance, since the measurement of marginal cost is an activity which requires a specialized knowledge of the engineering and technology of the industry (Turvey, 1969). In the next section, we deal with the relevant definition and interpretation of marginal cost. We then apply our definition to the measurement of marginal cost for a hypothetical, but realistic, wastewater system. In the last section, we make some observations about the design of wastewater tariffs

Spectral data for spin Higgs bundles

In this paper we determine the spectral data parametrizing Higgs bundles in a generic fiber of the Hitchin map for the case where the structure group is the special Clifford group with fixed Clifford norm. These are spin and "twisted" spin Higgs bundles. The method used relates variations in spectral data with respect to the Hecke transformations for orthogonal bundles introduced by Abe. The explicit description also recovers a result from the geometric Langlands program which states that the fibers of the Hitchin map are the dual abelian varieties to the corresponding fibers of the moduli spaces of projective orthogonal Higgs bundles (in the even case) and projective symplectic Higgs bundles (in the odd case)

Geochemistry of HASP, VLT, and other glasses from double drive tube 79001/2

The Apollo 17 double drive tube 79001/2 (station 9, Van Serg Crater) is distinctive because of its extreme maturity, abundance, and variety of glass clasts. It contains mare glasses of both high Ti and very low Ti (VLT) compositions, and highland glasses of all compositions common in lunar regolith samples: highland basalt (feldspathic; Al2O3 greater than 23 wt percent), KREEP (Al2O3 less than 23 wt percent, K2O greater than 0.25 wt percent), and low-K Fra Mauro (LKFM; Al2O3 less than 23 wt percent, K2O less than 0.25 wt percent). It also contains rare specimens of high-alumina, silica-poor (HASP), and ultra Mg glasses. HASP glasses contain insufficient SiO2 to permit the calculation of a standard norm, and are thought to be the product of volatilization during impact melting. They have been studied by electron microprobe major-element analysis techniques but have not previously been analyzed for trace elements. The samples analyzed for this study were polished grain mounts of the 90-160 micron fraction of four sieved samples from the 79001/2 core (depth range 2.3-11.5 cm). A total of 80 glasses were analyzed by SEM/EDS and electron microprobe, and a subset of 33 of the glasses, representing a wide range of compositional types, was chosen for high-sensitivity INAA. A microdrilling device removed disks (mostly 50-100 micron diameter, weighing approx. 0.1-0.5 micro-g) for INAA. Preliminary data reported here are based only on short counts done within two weeks of irradiation

Geologic Setting and Activity of Faults in the San Fernando Area, California

The faulting associated with the San Fernando earthquake of February 9, 1971, occurred in the Transverse Ranges structural province, a region noted for its strong and relatively young tectonic deformation. This is, however, the first example of historic surface faulting within the interior of that province

Altitude Investigation of Can-type Flame Holder in 20-inch-diameter Ram-jet Combustor

Altitude effects on can-type flameholder in ramjet combusto

On the Morgan-Shalen compactification of the SL(2,C) character varieties of surface groups

http://arxiv.org/PS_cache/math/pdf/9810/9810034v1.pdfA gauge theoretic description of the Morgan-Shalen compactification of the SL(2, C) character variety of the fundamental group of a hyperbolic surface is given in terms of a natural compactification of the moduli space of Higgs bundles via the Hitchin map